Live match not visible: active_matches/live_match_ids mismatch after arena restart

[ScavieFae]

Problem

The live match viewer shows no matches despite one actively playing.

GET /health
{"status":"ok","queue_size":0,"active_matches":1,"live_match_ids":[]}

active_matches comes from the DB (matches WHERE status = 'playing'), but live_match_ids comes from the in-memory _manager.match_info dict. After an arena restart (e.g. Railway redeploy), the DB retains the playing match but the WebSocket manager's in-memory state is lost.

The website uses live_match_ids to populate the viewer and the pulsing "LIVE" indicator in the header. With an empty array, both show nothing.

Root Cause

arena/server.py:863:

"live_match_ids": list(_manager.match_info.keys()),

_manager.match_info is populated only when a match_start WebSocket message arrives. If the arena restarts mid-match, this dict is empty even though the DB says a match is playing.

Suggested Fix

Fall back to the DB when _manager.match_info is empty:

live_ids = list(_manager.match_info.keys())
if not live_ids:
    # Recover from restart: use DB playing matches
    live_ids = db.get_playing_match_ids()

Or repopulate _manager.match_info on startup from DB state.

Impact

• Website live viewer shows "No live matches" despite match playing
• Header LIVE indicator doesn't pulse
• Spectators can't find the match

Owner: Scav (arena code)