fix: live flow real-time updates during processing (#861)

* fix: live flow real-time updates during processing

Three gaps caused transcript pages to require manual refresh after
live recording/processing:

1. UserEventsProvider only invalidated list queries on TRANSCRIPT_STATUS,
   not individual transcript queries. Now parses data.id from the event
   and calls invalidateTranscript for the specific transcript.

2. useWebSockets had no reconnection logic — a dropped WS silently
   killed all real-time updates. Added exponential backoff reconnection
   (1s-30s, max 10 retries) with intentional close detection.

3. No polling fallback — WS was single point of failure. Added
   conditional refetchInterval to useTranscriptGet that polls every 5s
   when transcript status is processing/uploaded/recording.

* feat: type-safe WebSocket events via OpenAPI stub

Define Pydantic models with Literal discriminators for all WS events
(9 transcript-level, 5 user-level). Expose via stub GET endpoints so
pnpm openapi generates TS discriminated unions with exhaustive switch
narrowing on the frontend.

- New server/reflector/ws_events.py with TranscriptWsEvent and UserWsEvent
- Tighten backend emit signatures with TranscriptEventName literal
- Frontend uses generated types, removes Zod schema and manual casts
- Fix pre-existing bugs: waveform mapping, FINAL_LONG_SUMMARY field name
- STATUS value now typed as TranscriptStatus literal end-to-end
- TOPIC handler simplified to query invalidation only (avoids shape mismatch)

* fix: restore TOPIC WS handler with immediate state update

The setTopics call provides instant topic rendering during live
transcription. Query invalidation still follows for full data sync.

* fix: align TOPIC WS event data with GetTranscriptTopic shape

Convert TranscriptTopic → GetTranscriptTopic in pipeline before
emitting, so WS sends segments instead of words. Removes the
`as unknown as Topic` cast on the frontend.

* fix: use NonEmptyString and TranscriptStatus in user WS event models

---------

Co-authored-by: Igor Loskutov <igor.loskutoff@gmail.com>

server/reflector/views/transcripts_websocket.py

@@ -4,18 +4,22 @@ Transcripts websocket API
 
 """
 
-from typing import Optional
-
-from fastapi import APIRouter, Depends, HTTPException, WebSocket, WebSocketDisconnect
+from fastapi import APIRouter, HTTPException, WebSocket, WebSocketDisconnect
 
 import reflector.auth as auth
 from reflector.db.transcripts import transcripts_controller
+from reflector.ws_events import TranscriptWsEvent
 from reflector.ws_manager import get_ws_manager
 
 router = APIRouter()
 
 
-@router.get("/transcripts/{transcript_id}/events")
+@router.get(
+    "/transcripts/{transcript_id}/events",
+    response_model=TranscriptWsEvent,
+    summary="Transcript WebSocket event schema",
+    description="Stub exposing the discriminated union of all transcript-level WS events for OpenAPI type generation. Real events are delivered over the WebSocket at the same path.",
+)
 async def transcript_get_websocket_events(transcript_id: str):
     pass
 
@@ -24,8 +28,9 @@ async def transcript_get_websocket_events(transcript_id: str):
 async def transcript_events_websocket(
     transcript_id: str,
     websocket: WebSocket,
-    user: Optional[auth.UserInfo] = Depends(auth.current_user_optional),
 ):
+    _, negotiated_subprotocol = auth.parse_ws_bearer_token(websocket)
+    user = await auth.current_user_ws_optional(websocket)
     user_id = user["sub"] if user else None
     transcript = await transcripts_controller.get_by_id_for_http(
         transcript_id, user_id=user_id
@@ -37,7 +42,9 @@ async def transcript_events_websocket(
     # use ts:transcript_id as room id
     room_id = f"ts:{transcript_id}"
     ws_manager = get_ws_manager()
-    await ws_manager.add_user_to_room(room_id, websocket)
+    await ws_manager.add_user_to_room(
+        room_id, websocket, subprotocol=negotiated_subprotocol
+    )
 
     try:
         # on first connection, send all events only to the current user

server/reflector/views/user_websocket.py

@@ -4,10 +4,22 @@ from fastapi import APIRouter, WebSocket, WebSocketDisconnect
 
 from reflector.auth.auth_jwt import JWTAuth  # type: ignore
 from reflector.db.users import user_controller
+from reflector.ws_events import UserWsEvent
 from reflector.ws_manager import get_ws_manager
 
 router = APIRouter()
 
+
+@router.get(
+    "/events",
+    response_model=UserWsEvent,
+    summary="User WebSocket event schema",
+    description="Stub exposing the discriminated union of all user-level WS events for OpenAPI type generation. Real events are delivered over the WebSocket at the same path.",
+)
+async def user_get_websocket_events():
+    pass
+
+
 # Close code for unauthorized WebSocket connections
 UNAUTHORISED = 4401