docs(01-03): complete Channel Gateway + Message Router plan

.planning/STATE.md

@@ -3,14 +3,14 @@ gsd_state_version: 1.0
 milestone: v1.0
 milestone_name: milestone
 status: planning
-stopped_at: Completed 01-foundation 01-04-PLAN.md
-last_updated: "2026-03-23T16:22:05.663Z"
+stopped_at: Completed 01-foundation 01-03-PLAN.md
+last_updated: "2026-03-23T16:34:38.175Z"
 last_activity: 2026-03-23 — Roadmap created, ready for Phase 1 planning
 progress:
   total_phases: 3
-  completed_phases: 0
+  completed_phases: 1
   total_plans: 4
-  completed_plans: 3
+  completed_plans: 4
   percent: 0
 ---
 
@@ -53,6 +53,7 @@ Progress: [░░░░░░░░░░] 0%
 | Phase 01-foundation P01 | 12 | 2 tasks | 32 files |
 | Phase 01-foundation P02 | 6 | 2 tasks | 15 files |
 | Phase 01-foundation P04 | 19 | 2 tasks | 25 files |
+| Phase 01-foundation P03 | 9 | 2 tasks | 20 files |
 
 ## Accumulated Context
 
@@ -74,6 +75,9 @@ Recent decisions affecting current work:
 - [Phase 01-foundation]: proxy.ts used instead of middleware.ts — Next.js 16 renamed middleware to proxy
 - [Phase 01-foundation]: standardSchemaResolver used over zodResolver — hookform/resolvers v5 dropped zod subpackage, uses Standard Schema protocol; zod v4 implements Standard Schema
 - [Phase 01-foundation]: Auth.js v5 JWT session strategy chosen — no portal_sessions DB table needed for Phase 1, stateless tokens sufficient
+- [Phase 01-foundation]: Patch at usage site in tests: mock 'gateway.channels.slack.resolve_tenant' not 'router.tenant.resolve_tenant' — Python name binding at import time
+- [Phase 01-foundation]: Celery payload extension: msg.model_dump() | extras dict, pop extras before model_validate in tasks.py to avoid pydantic validation errors on unknown fields
+- [Phase 01-foundation]: Bot token for chat.update loaded from channel_connections.config['bot_token'] in orchestrator task — keeps Slack SDK out of orchestrator package
 
 ### Pending Todos
 
@@ -85,6 +89,6 @@ None yet.
 
 ## Session Continuity
 
-Last session: 2026-03-23T16:22:05.661Z
-Stopped at: Completed 01-foundation 01-04-PLAN.md
+Last session: 2026-03-23T16:34:38.173Z
+Stopped at: Completed 01-foundation 01-03-PLAN.md
 Resume file: None