Phase 3 testing fixes: Fastify 5, SSE→WebSocket+FCM, enums, security, session lifecycle

- Upgrade Fastify 4→5 with all plugins (@fastify/websocket 11, cors 11, sensible 6)
- Migrate all SSE endpoints to WebSocket + FCM push (mitra chat requests, customer pairing status)
- Add flutter_local_notifications for foreground push notifications with sound
- Add splash screen to both apps (hide auth loading flash)
- Introduce constants/enums across entire codebase (no raw string literals)
- Move price tiers from hardcoded array to app_config DB (data-driven, includes 1-min test tier)
- Add session ownership validation on all shared chat routes
- Add ownership checks on endSession, respondToExtension, requestExtension
- Fix session timer: auto-complete expired/stale sessions on server restart
- Add 5-min grace period for abandoned closing sessions
- Fix extension flow: proper session_resumed handling, clearExtensionRequest, closure grace timer cleanup
- Fix chat screens: ConnectChat in initState, session status check on connect
- Fix customer expired view: 5-min countdown, closure state priority over expired state
- Fix mitra extension UI: loading spinner, disable buttons, handle EXTENSION_RESOLVED error
- Fix GoRouter navigation consistency (no more Navigator.pushNamed)
- Fix goodbye view keyboard overflow (SingleChildScrollView)
- Add active session card on customer home screen with refresh on navigate back
- Fix PricingBottomSheet extension mode (RequestExtension instead of new pairing)
- Send session_resumed to both parties on extension accept

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

requirement/phase3.md

@@ -14,6 +14,16 @@
 
 # Functional Requirement
 
+## Chat Opening
+Functinal Requirement:
+- Customer Application can start request chat session
+- Customer App will shows dialog to choose selection of time and price. This phase it will be mock only. later it will be taken from Configuration of Control Center
+- If enabled, Customer App will shows free trial instead of price selection. But this free trial only shows when following logic met:
+    * Free trial is enabled
+    * Customer never made any transaction (including free trial)
+- When customer choose Free trial, the chat session period will be determine by Control Center
+- After selection (either paid, or free trial), Backend will start pairing process
+
 ## Bi Directional Chat
 Functional requirement:
 - After pairing success, both Mitra and Customer can communicate bidirectional
@@ -22,17 +32,30 @@ Functional requirement:
 - All chat must be recorded in database in chronological order
 - When app is opened after shutdown, it must be able to populate all conversation along
 - User (both Mitra and Customer) must be able to re read all chat history
+- Each message will have sent (one check), delivered (double check) and read (double check with blue color) status
+- When one of the person type, application will shows typing indicator
 
 ## Chat Closure
-- Chat session is a limited time session. For now, it is 2 minutes, but make it configurable through control center
 - When chat is going to end (1 minutes left), shows remaining time on the chat screen
 - When chat session is finished there will be following functionality:
     - Customer Application:
         - Show dialog window whether Customer want to extend the session
         - If Customer do not want to extend, show closing message input
-    - 
-
+        - If Customer want to extend, show dialog selection of time and price. This phase it will be mock only. 
+        - Wait for Mitra confirmation, shows "Menunggu konfirmasi Bestie"
+            - If Mitra approve, prepare for payment process in this step
+            - If Mitra reject, show closing message input
+    - Mitra Application
+        - If customer do not want to extend, show closing message input
+        - If Customer extend, send confirmation to Mitra that customer want to extend for x minutes. Mitra can do following things:
+            - Accept, and session extended for x minutes
+            - Reject, show closing message input
 
+## Chat History
+Functional Requirement:
+- On Customer App, customer can see previous chat history, along with session information such as Mitra name (bestie name) and closure message
+- On Mitra App, mitra can see previous chat history, along with session information such as Customer name and closure message
+- Both will able to see communication history (chat message)