Add map record HUD announcements for T5 and T6

t5/NOTES.md

@@ -13,10 +13,16 @@ Copy all `tws_*.gsc` to `storage/t5/scripts/sp/` on the Plutonium T5 server
 
 ## Platform quirks (T5 SP engine, Plutonium)
 
+- **Initialize locals before loops when reading them afterwards.** T5 rejected
+  leaderboard's `chosen` variable at load time when its only assignment was
+  inside the map-search loop, even though its later use was guarded by the
+  match count. It now starts as `undefined` before that loop in both versions.
+  The JavaScript fixture harness and T6 compiler did not catch this T5 error.
 - **One `level waittill("connected")` only.** `tws_common` owns it. A
   second listener breaks the T5 SP connect handshake. Per-player work goes
-  through `tws_common::register_spawn_handler` and gets dispatched after
-  `spawned_player`.
+  through `tws_common::register_spawn_handler` after `spawned_player`, or
+  `register_connect_handler` for spectator-safe work after the dispatcher yields.
+  Leaderboard uses the latter; its level worker owns all HTTP work.
 - **Chat uses `level waittill("say", ...)`**, not `callbackPlayerSay`. T5 SP
   dedicated disables the sound subsystem, cascading through the say-callback
   dispatch — `callbackPlayerSay` never fires.
@@ -84,3 +90,4 @@ Copy all `tws_*.gsc` to `storage/t5/scripts/sp/` on the Plutonium T5 server
 | `tws_join`   | `.join` for spectators who have not played on this connection | — | `say`, `end_game`, `game_ended`, `intermission` |
 | `tws_lock`   | Lobby `g_password` lock at milestone round (`tws_lock_round`, default 20) | — | `hud_round_changed`, `hud_game_over` |
 | `tws_telemetry` | Ordered JSON game start, round, 30-second heartbeat, and game end reports with full player snapshots | `telemetry_queued`, `telemetry_finished` (internal) | `end_game`, `game_ended`, `intermission` |
+| `tws_leaderboard` | Cached completed-match map record and all tied holders, privately on join | — | `end_game`, `game_ended`, `intermission` |