fix: match both username formats in runs filter

Filter now matches both plain username and ActivityPub format
(@user@domain) to support runs created before and after the
actor ID change.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

server.py

@@ -837,8 +837,10 @@ async def ui_runs(request: Request):
     runs = list_all_runs()
 
     # Filter runs by user if logged in
+    # Match both plain username and ActivityPub format (@user@domain)
     if current_user:
-        runs = [r for r in runs if r.username == current_user]
+        actor_id = f"@{current_user}@{L2_DOMAIN}"
+        runs = [r for r in runs if r.username in (current_user, actor_id)]
 
     if not runs:
         if current_user: