infra(04-00): route /c/ → /client/, Dockerfile, Gitea deploy

- Rename src/app/c/[token] → src/app/client/[token]
- Update proxy.ts, ClientRow, admin client detail with /client/ path
- Add output: "standalone" to next.config.ts for Docker build
- Add Dockerfile (multi-stage, node:20-alpine) and .dockerignore
- Push schema to Coolify Postgres via SSH tunnel (drizzle-kit push ✓)
- Update CLAUDE.md constraint 4 to reflect /client/ route
- Add Phase 4 planning artifacts (04-00, 04-RESEARCH, 04-PATTERNS)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.planning/config.json

@@ -0,0 +1,15 @@
+{
+  "mode": "yolo",
+  "granularity": "coarse",
+  "parallelization": true,
+  "commit_docs": false,
+  "model_profile": "budget",
+  "workflow": {
+    "research": true,
+    "plan_check": true,
+    "verifier": true,
+    "nyquist_validation": false,
+    "auto_advance": false,
+    "_auto_chain_active": false
+  }
+}