feat: add webchat pwa push subscription support

docs/api/PROTOCOL.md

@@ -158,6 +158,12 @@ Exceptions (handled by their own trust/auth model and therefore bypass gateway t
 - `POST /google-chat/events` (Google Chat event callback, optional webhook token check)
 - `POST /bluebubbles/events` (BlueBubbles iMessage webhook callback, optional webhook token check)
 
+WebChat PWA push-subscription endpoints (auth-protected):
+- `GET /webchat/push/public-key` (returns enabled/configured push metadata)
+- `GET /webchat/push/subscriptions` (returns current subscription count/cap)
+- `POST /webchat/push/subscriptions` (registers/updates one browser subscription)
+- `DELETE /webchat/push/subscriptions` (removes one browser subscription by endpoint)
+
 ## Message Format
 
 ### Request (Client → Server)

docs/plans/state.json

@@ -5323,10 +5323,36 @@
         "docs/plans/state.json"
       ],
       "test_status": "pnpm test:run src/commands/builtin/index.test.ts src/daemon/routing.test.ts + pnpm typecheck passing"
+    },
+    "webchat-pwa-push-subscriptions-tier-b3": {
+      "status": "completed",
+      "date": "2026-02-18",
+      "updated": "2026-02-18",
+      "summary": "Implemented Tier B3 WebChat PWA baseline with service worker + manifest, browser push enable/disable controls in WebChat settings, and authenticated gateway subscription endpoints (`/webchat/push/*`) for storing/removing browser push subscriptions with VAPID public-key discovery.",
+      "files_modified": [
+        "src/config/schema.ts",
+        "src/config/schema.test.ts",
+        "src/daemon/services.ts",
+        "src/gateway/server.ts",
+        "src/gateway/server.test.ts",
+        "src/gateway/static.ts",
+        "src/gateway/ui/index.html",
+        "src/gateway/ui/app.js",
+        "src/gateway/ui/sw.js",
+        "src/gateway/ui/manifest.webmanifest",
+        "src/gateway/ui/flynn-icon.svg",
+        "src/gateway/ui/lib/pwa.js",
+        "src/gateway/ui/pages/settings.js",
+        "config/default.yaml",
+        "README.md",
+        "docs/api/PROTOCOL.md",
+        "docs/plans/state.json"
+      ],
+      "test_status": "pnpm test:run src/gateway/server.test.ts src/config/schema.test.ts + pnpm typecheck passing"
     }
   },
   "overall_progress": {
-    "total_test_count": 1911,
+    "total_test_count": 1913,
     "all_tests_passing": true,
     "p0_completion": "3/3 (100%)",
     "p1_completion": "4/4 (100%)",
@@ -5346,7 +5372,7 @@
     "gmail_auth_cli": "flynn gmail-auth command implemented with OAuth2 flow, doctor check, config routed to Telegram",
     "native_audio_support": "completed — smart routing for native audio (Gemini/OpenAI/GitHub) vs Whisper transcription fallback",
     "remaining_phases_completion": "Phase 1: 3/3 (100%) — context levels, command registry, memory structure. Phase 2: 3/3 (100%) — component registry, confidence routing, history index. Phase 3: 2/2 (100%) — adaptive memory/compaction, truthfulness/autonomy hardening",
-    "next_up": "Implement Tier B3 progressive web app push notifications for WebChat"
+    "next_up": "Implement Tier B1 guided onboarding improvement"
   },
   "soul_md_and_cron_create": {
     "date": "2026-02-11",