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

## Description:

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).

## Please complete the following:

- [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

src/client/controllers/LiveStatsController.ts

@@ -52,6 +52,8 @@ export class LiveStatsController implements Controller {
             gold: p.gold().toString(),
             isAlive: p.isAlive(),
             team: p.team(),
+            killedBy: p.killedBy(),
+            deathPosition: p.deathPosition(),
           },
         ];
       })

src/client/render/types/Renderer.ts

@@ -59,6 +59,8 @@ export interface PlayerState {
   smallID: number;
   isAlive: boolean;
   isDisconnected: boolean;
+  killedBy: string | null;
+  deathPosition: number | null;
   tilesOwned: number;
   gold: number;
   troops: number;

src/client/view/PlayerView.ts

@@ -76,6 +76,8 @@ function stateFromUpdate(pu: PlayerUpdate): PlayerState {
     smallID: pu.smallID!,
     isAlive: pu.isAlive!,
     isDisconnected: pu.isDisconnected!,
+    killedBy: pu.killedBy ?? null,
+    deathPosition: pu.deathPosition ?? null,
     tilesOwned: pu.tilesOwned!,
     gold: Number(pu.gold!),
     troops: pu.troops!,
@@ -454,6 +456,12 @@ export class PlayerView {
   isAlive(): boolean {
     return this.state.isAlive;
   }
+  killedBy(): string | null {
+    return this.state.killedBy;
+  }
+  deathPosition(): number | null {
+    return this.state.deathPosition;
+  }
   isPlayer(): this is PlayerView {
     return true;
   }