docs: implementation plan (TTY precedents folded in); task decomposition (17 tasks)

Plan updated with the alknet-tty findings: the drainer pattern
(single ordered writer) makes outbound chunk-boundary parsing sound;
TestStdinSink's try_send→Full→Pending is the inbound backpressure
precedent; OQ-01(a) now cites the reference.

Task graph (taskgraph-validated, 17 tasks, 6 generations, no cycles):
- tasks/server/: core-types, auth, healthz-decoy, adapter
- tasks/gateway/: dispatch, routes, publish
- tasks/websocket/: byte-adapter (research POC), upgrade-session, overlay-ops
- tasks/adapters/: from-openapi, from-jsonschema, to-openapi, from-wss, mcp
- tasks/client/: http-host
- tasks/infra/: integration-suite (phase 4)

Critical path runs through server core → adapter → WS session →
overlay tests → integration suite. High-risk tasks are the three WS
tasks, de-risked by the ws-byte-adapter POC blocking upgrade-session.

tasks/adapters/to-openapi.md

@@ -0,0 +1,44 @@
+---
+id: adapter-to-openapi
+name: to_openapi projection (6-endpoint gateway doc)
+status: pending
+depends_on: [gateway-routes]
+scope: moderate
+risk: low
+impact: component
+level: implementation
+tags: [adapters, phase-3]
+---
+
+## Description
+
+Port `adapters/to_openapi.rs` from
+`/workspace/@alkdev/alknet/crates/alknet-http/src/adapters/to_openapi.rs`:
+generate the OpenAPI doc describing the 6 fixed gateway endpoints
+(search/schema/call/batch/subscribe + publish), per-caller surface
+discovered via /search (not preloaded), `info.version` semver tracking
+the gateway contract (ADR-045; minor = /publish addition), error
+schemas projected per ADR-023. Wire `GET /openapi.json` in the server
+router. Pub ops excluded from /subscribe's tool description but listed
+in /search; /publish documents the NDJSON body per OQ-02's resolution.
+
+## Acceptance Criteria
+
+- [ ] Projection ported; 6-endpoint doc with correct versioning
+- [ ] /openapi.json serves it (integration test)
+- [ ] Doc validates against openapiv3 parsing
+- [ ] `cargo test` passes
+
+## References
+
+- docs/architecture/http-adapters.md (§to_openapi)
+- docs/architecture/decisions/042-openapi-gateway-pattern.md, 045-to-openapi-gateway-spec-versioning.md, 068-gateway-publish-endpoint.md
+- Old source: `/workspace/@alkdev/alknet/crates/alknet-http/src/adapters/to_openapi.rs`
+
+## Notes
+
+> Agent fills during implementation.
+
+## Summary
+
+> Agent fills on completion.