feat(players): app Players library and circular NPC tokens on scenes

Add userData players/teams, scene npcTokens with hex-inscribed sizing, session scale synced to presentation, and Playwright e2e coverage.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/renderer/shared/playerToken/useAppPlayers.ts

@@ -0,0 +1,24 @@
+import { useEffect, useState } from 'react';
+
+import { ipcChannels } from '../../../shared/ipc/contracts';
+import type { AppPlayer, AppPlayerTeam } from '../../../shared/types';
+import { getDndApi } from '../dndApi';
+
+export function useAppPlayers(): { players: AppPlayer[]; teams: AppPlayerTeam[] } {
+  const api = getDndApi();
+  const [players, setPlayers] = useState<AppPlayer[]>([]);
+  const [teams, setTeams] = useState<AppPlayerTeam[]>([]);
+
+  useEffect(() => {
+    void api.invoke(ipcChannels.players.list, {}).then((res) => {
+      setPlayers(res.players);
+      setTeams(res.teams);
+    });
+    return api.on(ipcChannels.players.stateChanged, ({ players: nextPlayers, teams: nextTeams }) => {
+      setPlayers(nextPlayers);
+      setTeams(nextTeams);
+    });
+  }, [api]);
+
+  return { players, teams };
+}