docs(tasks): close the wave-2 review gate — verdict green

Gate reading (commits b90e89b..196289f) against the architecture line
by line: ADR-001 mount contract, ADR-002 Config construction,
ADR-003 feature gates, ADR-004 dispositions, ADR-006 constraints,
mapping.md skeleton decline matrix per build, bounded resources, and
the harness — all confirmed. All four flagged interpretations
confirmed as recorded.

Fixed inline before committing (task-file hygiene only):

- w2-loopback-harness, w2-dispatch-decline-core: acceptance boxes
  checked once verified against the landed rows/runs
- w2-bounded-resources: stale placeholder lines removed
- review-wave-2: verdict recorded

Booked finding (next wave's decomposition): decline-path
tracing/observability — the reason a given wire decline carried is
currently docs-only (tracing unused in src/).

Verification: cargo test 104 rows green; --all-features green;
clippy ×2 -D warnings green; fmt clean; cargo doc 0 warnings;
taskgraph validate 19 tasks.

tasks/implementation/review-wave-2.md

@@ -1,7 +1,7 @@
 ---
 id: review-wave-2
 name: Wave 2 gate — the server-stack review
-status: pending
+status: completed
 depends_on: [w2-server-mount, w2-auth-bridge, w2-loopback-harness, w2-dispatch-decline-core, w2-spawn-return, w2-bounded-resources]
 scope: narrow
 risk: low
@@ -52,13 +52,13 @@ booked (remediation before wave 3 decomposes).
 
 ## Acceptance Criteria
 
-- [ ] Every ADR/mapping surface above read and confirmed (or
+- [x] Every ADR/mapping surface above read and confirmed (or
       corrected with the correction landed)
-- [ ] The spawn-and-return constraint verified as test-pinned;
+- [x] The spawn-and-return constraint verified as test-pinned;
       decline-first-alloc-never verified structurally
-- [ ] Full verification set green (`cargo test`, `--all-features`,
+- [x] Full verification set green (`cargo test`, `--all-features`,
       clippy ×2, fmt, `cargo doc --no-deps`)
-- [ ] Verdict recorded; wave 3 decomposition unblocked or findings
+- [x] Verdict recorded; wave 3 decomposition unblocked or findings
       booked
 
 ## References
@@ -69,8 +69,197 @@ booked (remediation before wave 3 decomposes).
 
 ## Notes
 
-> To be filled by implementation agent
+### Gate reading (line by line, 2026-10-28; commits b90e89b…196289f)
+
+- **ADR-001** ✓ — `SshAdapter::handle` is the mount: generic
+  `AsyncRead + AsyncWrite` stream in, the full russh stack per stream
+  via `run_stream`, returned **run to completion**
+  (`Result<(), AdapterError>` — the decision recorded in the task's
+  notes; no russh type rides the signature). No ALPN code, no relay
+  leg, no `alk/ssh` string anywhere in `src/`. The per-stream limits
+  posture holds: each mounted stream builds its own `SessionHandler`
+  over the serve-config, so the cap/timeout/window budget is
+  per-stream exactly as ADR-001's neutral consequence states.
+- **ADR-002** ✓ — the `Config` construction maps `Limits` one-for-one
+  (`window_size` / `maximum_packet_size` / `channel_buffer_size` /
+  `max_auth_attempts` verbatim; `inactivity_timeout` **always
+  `Some`** with a test pinning the default postures and a second
+  pinning the tunability); `methods` is built
+  `MethodSet::from(&[MethodKind::PublicKey][..])` with a test
+  asserting inequality against russh's `server_supported()` (honest
+  advertisement, not inherited); the pin is untouched (`0.65`,
+  `aws-lc-rs`, no `flate2`/`rsa`/`des`/`dsa`); the recorded
+  deliberations (`server_id` stays russh-default; keepalive stays
+  client-direction) are in the task's notes.
+- **ADR-003** ✓ — the wave-2 dispatch core is the feature graph's
+  first `cfg` consumer: flat, independent gates read via `cfg!`
+  predicates (`session ∨ git` for session channels;
+  `tunnel` for the three tunnel opens; `session` for pty/shell/pipe
+  rows; `git` for the git row); `default = []` declines everything
+  (none-build wire rows); x11 (open *and* request) and agent
+  forwarding decline unconditionally, never feature-gated; the `sftp`
+  feature gates nothing and the subsystem row declines in every
+  build (OQ-13 placeholder).
+- **ADR-004** ✓ — all dispositions in code as explicit hook
+  implementations: `auth_publickey` (ed25519-only gate checked on
+  **both** the signature algorithm and the key's algorithm before any
+  resolution → fingerprint → `resolve_from_fingerprint` →
+  accept-with-identity / reject fail-closed), the offered hook
+  accept-and-delegates, and the four non-publickey methods each have
+  an explicit reject body (never inherited). The bridge core
+  (`resolve_bridge`) takes no username parameter — OQ-03 holds
+  structurally; wire rows prove username-independence. Auth declines
+  are `Auth::Reject` dispositions end to end. The identity lands in
+  per-connection handler state
+  (`SessionHandler::resolved_identity`); its *session-level landing*
+  is wave-3 assertion territory (flagged in the task's notes — code
+  verifiable only through `auth_succeeded` consumption), confirmed as
+  correctly deferred.
+- **ADR-006** ✓ — parse-only dispatch with no detect residue (the
+  SOCKS-detect is gone; a request-less session channel serves
+  nothing by construction — no serving path exists outside the
+  request hooks); decline-first-alloc-never verified structurally:
+  every open-level decline answers before any accept; the only
+  pre-decline resource on any request path is none (exec parses via a
+  pure fn first), and the spawned serving paths' only allocation is
+  the post-decision handle clone; spawn-and-return is **pinned by
+  test, not convention** — the `serve.rs` unit row (spawn returns
+  while the path is pending) plus the two wire rows
+  (`tests/spawn_return.rs`: handler-returns-fast under follow-up
+  traffic with the spawn still gated; exit-status strictly before
+  close, timestamps proving the report outlived the handler's
+  return).
+- **mapping.md** ✓ — the skeleton decline-matrix rows are green per
+  build through the harness
+  (`tests/dispatch_core.rs`: shared rows in every build; per-build
+  modules cfg-pinned to exactly one feature combination so no
+  git-only row runs under `--all-features` by accident; each row
+  carried a `Contract stamp:`). Wire decline reasons are
+  vanilla-observable: open-level declines answer failure codes
+  (`AdministrativelyProhibited` / the tunnel stub's `ConnectFailed`),
+  request-level capability declines answer `channel_failure` with
+  the channel provably still usable.
+- **Bounded resources** ✓ — the in-crate cap is enforced at the
+  handler surface, recovering on close (wire row: cap reached →
+  decline; close → open succeeds again, deterministic on the FIFO
+  wire ordering; zero-cap row refuses everything without poisoning);
+  the tunnel rows cap-gate before the stub so a declined stub cannot
+  leak a count; `max_auth_attempts` verified behaviorally on the wire
+  (ceiling → `NoMoreAuthMethodsAvailable` disconnect with the empty
+  remaining-set shape); the size/window/clock knobs recorded as
+  config-mapping-covered and the keepalive posture pinned by the
+  harness row; `max_exec_command_len` correctly carried-not-enforced
+  (wave-3 grammar's consumption, per the plan bullet). No unbounded
+  shape anywhere: accepted-but-unserved session channels hold bounded
+  buffers only (window/buffer knobs).
+- **The harness** ✓ — the contract-test vehicle convention
+  established exactly as the task pinned it: tokio-duplex transport
+  + `connect_stream` (decision recorded in the module docs, over TCP
+  loopback), sibling-of-the-doubles placement under `tests/common/`,
+  the `drive` vocabulary the wave-3 mappings inherit, and the wave-1
+  doubles exercised live through it (`MemIdentityProvider`,
+  `MemHostKeySource`, `MemHostKeyPolicy` both verdicts, fixture
+  plumbing) — the acceptance row
+  (`in_process_pair_connects_and_authenticates_end_to_end`) plus the
+  auth-bridge and dispatch rows all ride it.
+- **Docs honesty** ✓ — the handler module docs state precisely what
+  is deliberately not here (the family seams, the client direction,
+  the store-and-take handoff, the wave-3 tunnel accept-flow), each
+  seam stub documents its wave-3 replacement point, and the
+  inherited-posture note (the bare `auth-agent` /
+  `forwarded-streamlocal` channel types decline via russh's own
+  inline rejection at this pin — flagged as an upstream watch item, a
+  pin bump that changed it would surface as accepted-then-dropped) is
+  recorded rather than silently relied on.
+- **The wave-1 gate's lesson absorbed** ✓ — `cargo doc --no-deps`
+  ran clean on this gate (0 warnings), and `taskgraph validate` passes.
+
+### Interpretations (flagged for this gate) — all confirmed
+
+1. **Git-parseability probe is skeleton-level** — confirmed:
+   `classify_exec` carries service-prefix + path-shape only, its
+   module docs name the wave-3 replacement explicitly, and the probe
+   rows pin exactly the POC-3 stage-A facts the skeleton needs
+   (unknown service → pipe row; total over arbitrary input).
+2. **Routing stubs decline at the family-seam boundary, documented as
+   skeleton** — confirmed: the stub bodies are the named wave-3
+   replacement points (`git_row_stub` … `tunnel_row_stub`), the
+   serving-path decline shape (failure then close) is wire-pinned,
+   and the tunnel stub's `ConnectFailed` reason matches ADR-006
+   decision 1's fail shape.
+3. **Adapter error surface shaped in `w2-server-mount`** — confirmed:
+   `AdapterError` is the closed two-class taxonomy
+   (`Construction(#[from] KeySourceError)` + `Wire(#[from]
+   russh::Error)`) with the locked→no-server rule at construction and
+   no catch-all; the wire decline reasons landed in the dispatch, not
+   in the error taxonomy (the wave-1 reservation spent correctly).
+4. **Harness transport and placement pinned in
+   `w2-loopback-harness`** — confirmed, recorded in its module docs.
+
+### Minor issues found and fixed inline (this session)
+
+Doc-hygiene only, in the task files (no `src/` change warranted):
+
+- `w2-loopback-harness.md` and `w2-dispatch-decline-core.md`:
+  acceptance-criteria boxes still `[ ]` despite `status: completed`
+  → checked (verified against the landed rows and runs).
+- `w2-bounded-resources.md`: stale `> To be filled…` placeholder
+  lines above already-filled Notes/Summary content → removed.
+- `review-wave-2.md` (this file): placeholder lines removed; verdict
+  recorded.
+
+### Booked findings (folded into the next waves, no remediation this gate)
+
+- **No observability instrumentation on the decline paths.** The
+  request-level decline class's "reason" is currently only the
+  routing decision documented per build — nothing server-side logs
+  which reason a given wire decline carried (`tracing` is in the
+  manifest per the ADR-002 toolkit but unused in `src/` so far). Small
+  follow-up task for the next wave's decomposition (alongside the
+  real serving paths, where serve/decline path tracing matters more
+  than in the stub wave): decline-path tracing events with the
+  deciding context (row + feature build + channel), and a check of
+  the family's tracing conventions before choosing the event shape.
+- Carried forward, already documented (not new findings): the
+  non-exhaustive-arg auth hooks are wire-testable only (resolves at
+  wave 3's `auth_succeeded` consumption); `forwarded-tcpip` wire rows
+  need the wave-3 acceptor vocabulary; the `streamlocal`/
+  `direct-streamlocal` runtime-Unix gate rides the wave-3 serving
+  flow.
+
+No shape errors found in the mount signature, the auth-bridge state,
+or the dispatch routing — the three churn-critical surfaces this gate
+exists to protect.
+
+### Verification (all green)
+
+`cargo test` 104 rows across 7 binaries + doctests ·
+`cargo test --all-features` (60 lib + integration rows) ·
+`cargo clippy --all-targets -- -D warnings` ✓ ·
+`cargo clippy --all-features --all-targets -- -D warnings` ✓ ·
+`cargo fmt --check` ✓ · `cargo doc --no-deps` 0 warnings ·
+`taskgraph validate` ✓ (19 tasks).
 
 ## Summary
 
-> To be filled on completion
+**Verdict: green.** The wave-2 server stack reads clean against the
+architecture line by line: ADR-001's mount contract (generic stream,
+full russh stack per stream, run-to-completion `Result<(),
+AdapterError>`, edge termination only), ADR-002's Config construction
+(exactly `{publickey}` advertisement, one-for-one knob mapping,
+always-set wall clock, pin untouched), ADR-003's feature graph as the
+dispatch's first `cfg` consumer (flat, `default = []` declines
+everything, x11/auth-agent never gated), ADR-004's dispositions as
+explicit hook code (ed25519-only fingerprint bridge, four explicit
+declines, username structurally excluded), ADR-006's constraints
+parse-only dispatch, decline-first-alloc-never structural, and
+spawn-and-return pinned by test over the real wire — plus the bounded
+in-crate channel cap enforced and recovering at the handler surface,
+the skeleton decline-matrix rows green per feature build through the
+loopback harness, and docs that state what is deliberately deferred.
+All four flagged interpretations confirmed as recorded; minor
+task-file hygiene fixed inline; one small finding booked
+(decline-path tracing/observability, next wave). Wave 3 decomposition
+is unblocked and should absorb: the booked tracing task, the harness
+acceptor/vocabulary needs, and the deferred identity-landing
+assertion at wave 3's `auth_succeeded`.

tasks/implementation/w2-bounded-resources.md

@@ -61,8 +61,6 @@ not from this task.
 
 ## Notes
 
-> To be filled by implementation agent
-
 - **The count is handler-owned, not locked.** New private module
   `src/channel_cap.rs` (`ChannelCap`): the per-session active-channel
   count with `admit` (check+increment at accept sites) / `has_room`
@@ -136,8 +134,6 @@ not from this task.
 
 ## Summary
 
-> To be filled on completion
-
 Landed the in-crate concurrent-channel cap at the handler surface:
 new private `channel_cap` module (count + admit/release semantics,
 unit-tested), wired into `SessionHandler`'s every open hook — the

tasks/implementation/w2-dispatch-decline-core.md

@@ -61,21 +61,21 @@ declining stubs this task shapes the routes for.
 
 ## Acceptance Criteria
 
-- [ ] Every `channel_open_*` hook gates per the feature graph;
+- [x] Every `channel_open_*` hook gates per the feature graph;
       x11/auth-agent decline in every build; unfeatured types decline
       at open with clean wire reasons
-- [ ] `exec_request` takes the parse path (git-parseable → git row,
+- [x] `exec_request` takes the parse path (git-parseable → git row,
       else → session pipe row) before any allocation; request-less
       session channels decline as unfeatured per ADR-006
-- [ ] `subsystem_request` declines-with-reason for `sftp` (OQ-13
+- [x] `subsystem_request` declines-with-reason for `sftp` (OQ-13
       placeholder) and git service names; `env_request` declines
       unconditionally (OQ-09)
-- [ ] Decline-first-alloc-never holds structurally (declines precede
+- [x] Decline-first-alloc-never holds structurally (declines precede
       any channel/resource allocation on every path)
-- [ ] Feature-gated code paths exercised per build (`cargo test
+- [x] Feature-gated code paths exercised per build (`cargo test
       --features git/session/tunnel` rows + `--all-features`); the
       skeleton decline-matrix rows green through the harness
-- [ ] `cargo test`, `cargo clippy --all-targets -- -D warnings`,
+- [x] `cargo test`, `cargo clippy --all-targets -- -D warnings`,
       `cargo clippy --all-features --all-targets -- -D warnings`,
       `cargo fmt --check` pass
 

tasks/implementation/w2-loopback-harness.md

@@ -46,17 +46,17 @@ the wave-1 doubles work live through the wave-2 stack.
 
 ## Acceptance Criteria
 
-- [ ] In-process server/client pair connects and authenticates end to
+- [x] In-process server/client pair connects and authenticates end to
       end (fixture key → `MemIdentityProvider` → authenticated
       session) with no TCP port dependency (or the TCP choice
       recorded, if taken)
-- [ ] Harness helpers cover: auth (success + failure observation),
+- [x] Harness helpers cover: auth (success + failure observation),
       channel open (success + open-failure reason), session requests
       (success/failure), exit-status/close observation
-- [ ] The transport choice and module placement are recorded
-- [ ] The harness is documented as the contract-test vehicle; the
+- [x] The transport choice and module placement are recorded
+- [x] The harness is documented as the contract-test vehicle; the
       wave-1 doubles are exercised live through it
-- [ ] `cargo test`, `cargo clippy --all-targets -- -D warnings`,
+- [x] `cargo test`, `cargo clippy --all-targets -- -D warnings`,
       `cargo fmt --check` pass
 
 ## References