feat(livestats): per-player killedBy + deathPosition + winner for live standings (#4593)

Enriches the admin-bot live-stats snapshot
(`/api/adminbot/game/:id/stats`) with the per-player fields a semi-live
standings board needs, so it can score kills + placement live instead of
waiting for the post-game record.

Per player in `liveStats.players[]`:
- **`killedBy`** — the eliminator's clientID (null while alive /
non-client killer). Invert → live kill points.
- **`deathPosition`** — finishing place at elimination = non-bot players
still standing + 1 (frozen at "last of the then-standing"). Null while
alive → live placement.

The **full roster** is reported (dead players are retained in the client
view), plus top-level **`winner`** (the decided winner's clientID, else
null).

Deterministic / consensus-safe: `killedBy` (stamped at `recordKill`) and
`deathPosition` (stamped in `PlayerExecution`) are pure sim values, so
in-sync clients agree on the majority vote; `winner` is added
server-side in `GameServer.liveStats()` from the winner vote (like the
existing publicID/username/connected enrichment).

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory

tests/server/LiveStats.test.ts

@@ -63,6 +63,8 @@ describe("GameServer.handleLiveStats", () => {
       gold: "100",
       isAlive: true,
       team: null,
+      killedBy: null,
+      deathPosition: null,
     },
   ];
 
@@ -89,6 +91,7 @@ describe("GameServer.handleLiveStats", () => {
     // 2 of 3 IPs -> consensus.
     expect(game.liveStats()).toEqual({
       turn: 100,
+      winner: null,
       players: [
         {
           ...players[0],
@@ -151,6 +154,7 @@ describe("GameServer.handleLiveStats", () => {
     report(game, clients[1], 200, snapshot(42));
     expect(game.liveStats()).toEqual({
       turn: 200,
+      winner: null,
       players: [
         {
           ...snapshot(42)[0],