docs(arch): AlknetClient native dial seam — resolves OQ-55 (ADR-089)

Extract the deferred AlknetClient as a new crate alknet-client — the
client-side analogue of AlknetEndpoint. Three dial methods (QUIC +
TCP+TLS via TlsClientConfig, iroh via key) produce a Connection for
CallClient::spawn_dispatch / ChannelClient::from_connection to consume.
The deferral collapsed because ADR-086 gave the native endpoint type
three dial shapes within one endpoint type, ADR-087 broke the circular
hedge, and ADR-083 gave the server-side shape to mirror by symmetry.

Names the three concept layers that were tangled throughout the initial
development (deployment role / establishment side / ALPN-level category)
so the fix is legible. Names alknet/register as a dialable entry-point
ALPN (native registration, parallel to HTTP registration in OQ-58); its
wire protocol is deferred to OQ-66 (blocked on OQ-58's token model).

Cross-references updated across 11 existing docs (README, overview,
open-questions, OQ-55, tls, hub, core, channels README/overview/
channel-client, call client-and-adapters) to reflect OQ-55 resolved and
the new alknet-client crate. Architecture review passed (2 critical, 7
warnings — all addressed).

docs/architecture/crates/channels/README.md

@@ -39,7 +39,7 @@ protocol work itself.
 | [077](../../decisions/077-tty-inside-channels.md) | TTY Inside Channels — Sub-Streams, Not Wire Format | TTY's two modes (direct vs channels); 5 sub-streams; control bidirectional via 3/4; amends ADR-052 scope |
 | [078](../../decisions/078-two-pump-shutdown-on-completion.md) | Two-Pump Shutdown-on-Completion Pattern | The two-pump deadlock contract; handler-level, not channels-layer |
 | [079](../../decisions/079-hub-relay-translate-not-forward.md) | Hub Relay — Translate, Not Transparently Forward | The hub translates channel 0, byte-forwards data channels with ID rewrite |
-| [080](../../decisions/080-channelclient.md) | ChannelClient — the Client Side of a Channels Connection | `ChannelClient`, transport-agnostic `from_connection` primary + `connect_quic` convenience; `AlknetClient` dial-seam deferred (OQ-55) |
+| [080](../../decisions/080-channelclient.md) | ChannelClient — the Client Side of a Channels Connection | `ChannelClient`, transport-agnostic `from_connection` primary + `connect_quic` convenience; `AlknetClient` dial-seam extracted (ADR-089, resolves OQ-55) |
 | [081](../../decisions/081-channels-subcrate-decomposition.md) | channels Sub-Crate Decomposition | `channels-core` (pure multiplexer) / `channels-call` (call coupling + ChannelClient); hub and worker are consumers, not sub-crates |
 | [070](../../decisions/070-bidistreamsource-trait.md) | BidiStreamSource Trait | The `Connection` extension point `ChannelBidiStreamSource` implements |
 | [065](../../decisions/065-connection-from-stream-generic-single-stream.md) | `Connection::from_stream` | The transport-agnostic `Connection` the channels layer rides on |
@@ -52,7 +52,7 @@ protocol work itself.
 
 | OQ | Title | Status | Relevance |
 |----|-------|--------|-----------|
-| OQ-55 | AlknetClient / Client Establishment Extraction | deferred(scope) | `ChannelClient`'s API is decided (ADR-080): transport-agnostic `from_connection` primary, `connect_quic` convenience. `AlknetClient` core extraction stays deferred — blocked on a second *transport's* dial (the shared dial+TLS seam), not a second client |
+| OQ-55 | AlknetClient / Client Establishment Extraction | resolved (ADR-089) | `ChannelClient`'s API is decided (ADR-080): transport-agnostic `from_connection` primary, `connect_quic` convenience. `AlknetClient` core extraction is now resolved — the native dial seam is `alknet-client` (ADR-089) |
 | OQ-56 | Full channel-level flow-control windowing | deferred(scope) | Bounded-buffer is decided (ADR-076); full windowing is an extension blocked on "a real deployment observes HOL blocking on a saturated channel where bounded buffer is insufficient" |
 | OQ-57 | Two-pump helper extraction to alknet-core | deferred(scope) | The shutdown-on-completion *contract* is decided (ADR-078); the *helper* extraction is blocked on a second two-pump handler existing (shape convergence) |
 

docs/architecture/crates/channels/channel-client.md

@@ -159,27 +159,24 @@ populates what operations they expose).
 name follows the `CallClient` convention (the side that dialed), not a
 request/response role.
 
-## Relationship to `AlknetClient` (OQ-55 — deferred)
+## Relationship to `AlknetClient` (ADR-089 — resolved)
 
 `ChannelClient`'s *API* is transport-agnostic — `from_connection` takes a
-pre-established `Connection`. What is deferred (OQ-55) is the shared
-*dial+TLS* seam (`AlknetClient`): the transport-specific work each dial
-helper does — open a socket, run the TLS handshake, apply ADR-034's
-verifier-selection rule, produce a `Connection`. That dial is genuinely
-transport-specific (QUIC, TCP+TLS, WebTransport, raw TCP, SSH), and we have
-one shape implemented (QUIC, in `connect_quic`). Extracting a QUIC-shaped
-connector now and naming it `AlknetClient` would bake QUIC in as *the*
-establishment shape — the same welding ADR-065 unwound on the server side.
+pre-established `Connection`. The shared *dial+TLS* seam
+(`AlknetClient`, OQ-55) is now extracted: [`alknet-client`](../client/README.md)
+provides `AlknetClient` with three dial methods (`dial_quic` /
+`dial_tcp_tls` / `dial_iroh`), each producing a `Connection` that
+`from_connection` consumes. The dial is transport-specific (QUIC,
+TCP+TLS, iroh); the take-over (`from_connection`) is
+transport-agnostic. The two concerns are separated.
 
-This is why `from_connection` is the one-way-door surface and
-`connect_quic` is a two-way-door convenience over it. `AlknetClient` (when
-extracted, after a second transport's dial exists) becomes the shared
-*dial*; `from_connection` stays the shared *channels-take-over*. The two
-concerns are separated now, before the one-way-door API is cast.
-
-The friction while `AlknetClient` is deferred is duplicated
-verifier-selection boilerplate across dial helpers (~20 lines each) — not
-duplicated capability and not a QUIC-welded client API.
+`connect_quic` becomes a thin wrapper over `AlknetClient::dial_quic` —
+dial QUIC, then `from_connection`. A caller that needs transport
+selection (QUIC with TCP+TLS fallback) uses `AlknetClient` directly;
+the fallback policy is a caller concern. See
+[ADR-089](../../decisions/089-alknetclient-native-dial-seam.md) for the
+full decision and [OQ-55](../../questions/055-alknetclient-establishment-extraction.md)
+(resolved).
 
 ## Design Decisions
 
@@ -187,14 +184,15 @@ All design decisions are documented as ADRs in [decisions/](../../decisions/).
 
 | ADR | Decision | Summary |
 |-----|----------|---------|
-| [080](../../decisions/080-channelclient.md) | ChannelClient | Client side; transport-agnostic `from_connection` primary, `connect_quic` convenience; `AlknetClient` dial-seam deferred (OQ-55) |
+| [080](../../decisions/080-channelclient.md) | ChannelClient | Client side; transport-agnostic `from_connection` primary, `connect_quic` convenience; `AlknetClient` dial-seam extracted (ADR-089, resolves OQ-55) |
 
 ## Open Questions
 
-- **OQ-55** (deferred(scope)): `AlknetClient` core **dial+TLS seam**
-  extraction — blocked on a second *transport's* dial. `ChannelClient`'s
-  API is transport-agnostic (`from_connection`); the deferred part is the
-  shared *dial* across transports, not the channels protocol.
+- **OQ-55** (resolved by ADR-089): `AlknetClient` core **dial+TLS seam**
+  — extracted as `alknet-client` with three dial methods.
+  `ChannelClient`'s API is transport-agnostic (`from_connection`); the
+  dial is the shared seam, now extracted. See
+  [ADR-089](../../decisions/089-alknetclient-native-dial-seam.md).
 
 ## References
 

docs/architecture/crates/channels/overview.md

@@ -249,7 +249,7 @@ All design decisions are documented as ADRs in [decisions/](../../decisions/).
 | [077](../../decisions/077-tty-inside-channels.md) | TTY Inside Channels | Two modes (direct vs channels); 5 sub-streams; control bidirectional via 3/4 |
 | [078](../../decisions/078-two-pump-shutdown-on-completion.md) | Two-Pump Pattern | Shutdown-on-completion contract; handler-level |
 | [079](../../decisions/079-hub-relay-translate-not-forward.md) | Hub Relay | Translate channel 0, byte-forward data channels with ID rewrite |
-| [080](../../decisions/080-channelclient.md) | ChannelClient | Client side; transport-agnostic `from_connection` primary, `connect_quic` convenience; `AlknetClient` dial-seam deferred (OQ-55) |
+| [080](../../decisions/080-channelclient.md) | ChannelClient | Client side; transport-agnostic `from_connection` primary, `connect_quic` convenience; `AlknetClient` dial-seam extracted (ADR-089, resolves OQ-55) |
 | [081](../../decisions/081-channels-subcrate-decomposition.md) | Sub-Crate Decomposition | `channels-core` (pure multiplexer) / `channels-call` (call coupling + ChannelClient); hub and worker are consumers |
 
 ## Open Questions
@@ -257,10 +257,11 @@ All design decisions are documented as ADRs in [decisions/](../../decisions/).
 Open questions are tracked in [open-questions.md](../../open-questions.md).
 Key questions affecting this crate:
 
-- **OQ-55** (deferred(scope)): `AlknetClient` core **dial+TLS seam**
-  extraction — blocked on a second *transport's* dial. `ChannelClient`'s
-  API is transport-agnostic (`from_connection`); `AlknetClient` is the
-  shared *dial* across transports, not the channels protocol.
+- **OQ-55** (resolved by ADR-089): `AlknetClient` core **dial+TLS seam**
+  — extracted as `alknet-client` with three dial methods.
+  `ChannelClient`'s API is transport-agnostic (`from_connection`); the
+  dial is the shared seam, now extracted. See
+  [ADR-089](../../decisions/089-alknetclient-native-dial-seam.md).
 - **OQ-56** (deferred(scope)): Full channel-level flow-control windowing —
   bounded-buffer is decided (ADR-076); full windowing is an extension
   blocked on a real HOL-blocking deployment observation.