Decompose Phase 2 (Core Bridge) into 8 dependency-ordered tasks

Phase 2 completes the interface-to-protocol bridge and adds core types
that external crates depend on. The 8 tasks are organized into 5
generations with clear dependencies:

- Gen 1: StreamInterface/MessageInterface trait split (must go first)
- Gen 2: SshSession bridge, RawFraming impl, CredentialProvider (parallel)
- Gen 3: API keys in DynamicConfig (depends on CredentialProvider)
- Gen 4: ListenerConfig HTTP/DNS stubs + axum scaffold
- Gen 5: Review gate before Phase 3

Key design decisions:
- 2.4a/2.4b split: SecretStoreCredentialProvider deferred to Phase 3
- API keys (2.6) must land before axum scaffold (2.7)
- ListenerConfig (2.5) must land before axum scaffold (2.7)
- Gen 2 tasks are parallelizable (separate modules)

tasks/integration/phase2/review-core-bridge-phase2.md

@@ -0,0 +1,61 @@
+---
+id: review-core-bridge-phase2
+name: Review all Phase 2 changes for spec conformance and prepare for Phase 3
+status: pending
+depends_on: [stream-interface-message-interface-split, ssh-session-call-protocol-bridge, raw-framing-interface-implementation, credential-provider-trait, api-keys-dynamic-config, listenconfig-http-dns-stubs, axum-http-router-scaffold]
+scope: narrow
+risk: low
+impact: phase
+level: review
+---
+
+## Description
+
+Review all Phase 2 implementation for spec conformance, architectural consistency, and completeness before Phase 3 crate development begins. Per integration plan section 4.5, a second doc sync should capture any deviations between spec and implementation.
+
+This review covers:
+1. **Spec conformance**: Do implementations match the architecture docs and ADRs (035, 036, 037)?
+2. **Layer boundary discipline**: Does every component belong to exactly one layer? No call protocol logic in the interface layer, no interface logic in the transport layer.
+3. **Terminology consistency**: head/worker everywhere (no hub/spoke), StreamInterface/MessageInterface (no bare "Interface" trait), consistent naming.
+4. **Test coverage**: Do all Phase 2 tasks have tests that verify acceptance criteria?
+5. **No circular dependencies**: alknet-core doesn't depend on alknet-secret, alknet-storage, or alknet-flowgraph.
+6. **Doc sync**: Update architecture docs to reflect Phase 2 implementation state. Specifically:
+   - `interface.md` — StreamInterface/MessageInterface split, InterfaceRequest/InterfaceResponse
+   - `auth.md` — API keys, resolve_from_token() changes
+   - `configuration.md` — DynamicConfig additions (api_keys, credentials)
+   - `call-protocol.md` — SshSession bridge, RawFraming auth flow
+   - Any deviations between spec and implementation should be documented
+
+## Acceptance Criteria
+
+- [ ] All Phase 2 tasks have acceptance criteria verified (each task's AC checklist is complete)
+- [ ] Layer boundaries are clean: interface layer produces/consumes `InterfaceEvent`; protocol layer handles `EventEnvelope`; transport layer provides byte streams
+- [ ] No `Interface` trait references remain (all renamed to `StreamInterface`)
+- [ ] No `TransportKind::Dns` in the enum (DNS is a `MessageInterface`)
+- [ ] `Cargo.toml` dependency check: alknet-core has no circular deps on external crates
+- [ ] `http` feature flag correctly gates axum dependency
+- [ ] Architecture docs updated for Phase 2 state:
+  - [ ] `interface.md` reflects StreamInterface/MessageInterface split
+  - [ ] `auth.md` reflects API keys in DynamicConfig
+  - [ ] `configuration.md` reflects new DynamicConfig sections
+  - [ ] `call-protocol.md` reflects functional SshSession bridge
+- [ ] All tests pass: `cargo test --all-features`
+- [ ] No compiler warnings on Phase 2 code
+- [ ] `taskgraph parallel --path tasks/integration/phase2` shows all tasks completed
+
+## References
+
+- docs/research/integration-plan.md — Phase 4.5 doc sync
+- All Phase 2 ADRs: 035, 036, 037
+- All Phase 2 implementation tasks (2.1–2.7)
+- docs/architecture/ — architecture docs to update
+
+## Notes
+
+> This is a quality gate before Phase 3. The review should be thorough but shouldn't block on minor documentation phrasing. Focus on structural conformance: are layers respected, are traits correct, are dependencies acyclic?
+
+> If any deviations between spec and implementation are found, document them in the relevant architecture doc with a "Deviation from spec" note explaining why.
+
+## Summary
+
+> To be filled on completion