feat: implement full backend + frontend server detail, settings, and create server pages

Backend:
- Complete FastAPI backend with 42+ REST endpoints (auth, servers, config,
  players, bans, missions, mods, games, system)
- Game adapter architecture with Arma 3 as first-class adapter
- WebSocket real-time events for status, metrics, logs, players
- Background thread system (process monitor, metrics, log tail, RCon poller)
- Fernet encryption for sensitive config fields at rest
- JWT auth with admin/viewer roles, bcrypt password hashing
- SQLite with WAL mode, parameterized queries, migration system
- APScheduler cleanup jobs for logs, metrics, events

Frontend:
- Server Detail page with 7 tabs (overview, config, players, bans,
  missions, mods, logs)
- Settings page with password change and admin user management
- Create Server wizard (4-step; known bug: silent validation failure)
- New hooks: useServerDetail, useAuth, useGames
- New components: ServerHeader, ConfigEditor, PlayerTable, BanTable,
  MissionList, ModList, LogViewer, PasswordChange, UserManager
- WebSocket onEvent callback for real-time log accumulation
- 120 unit tests passing (Vitest + React Testing Library)

Docs:
- Added .gitignore, CLAUDE.md, README.md
- Updated FRONTEND.md, ARCHITECTURE.md with current implementation state
- Added .env.example for backend configuration

Known issues:
- Create Server form: "Next" buttons don't validate before advancing,
  causing silent submit failure when fields are invalid
- Config sub-tabs need UX redesign for non-technical users

backend/core/dal/player_repository.py

@@ -0,0 +1,70 @@
+import json
+from datetime import datetime, timezone
+from core.dal.base_repository import BaseRepository
+
+
+class PlayerRepository(BaseRepository):
+
+    def get_all(self, server_id: int) -> list[dict]:
+        return self._fetchall(
+            "SELECT * FROM players WHERE server_id = :sid ORDER BY slot_id",
+            {"sid": server_id},
+        )
+
+    def count(self, server_id: int) -> int:
+        row = self._fetchone(
+            "SELECT COUNT(*) as cnt FROM players WHERE server_id = :sid",
+            {"sid": server_id},
+        )
+        return row["cnt"] if row else 0
+
+    def upsert(self, server_id: int, player: dict) -> None:
+        now = datetime.now(timezone.utc).isoformat()
+        self._execute(
+            """
+            INSERT INTO players (server_id, slot_id, name, guid, ip, ping, game_data, joined_at, updated_at)
+            VALUES (:sid, :slot, :name, :guid, :ip, :ping, :gd, :now, :now)
+            ON CONFLICT(server_id, slot_id) DO UPDATE SET
+                name = excluded.name,
+                guid = excluded.guid,
+                ping = excluded.ping,
+                game_data = excluded.game_data,
+                updated_at = excluded.updated_at
+            """,
+            {
+                "sid": server_id,
+                "slot": str(player.get("slot_id", "")),
+                "name": player.get("name", ""),
+                "guid": player.get("guid"),
+                "ip": player.get("ip"),
+                "ping": player.get("ping"),
+                "gd": json.dumps(player.get("game_data", {})),
+                "now": now,
+            },
+        )
+
+    def clear(self, server_id: int) -> None:
+        self._execute("DELETE FROM players WHERE server_id = :sid", {"sid": server_id})
+
+    def get_history(
+        self,
+        server_id: int,
+        limit: int = 50,
+        offset: int = 0,
+        search: str | None = None,
+    ) -> tuple[int, list[dict]]:
+        conditions = ["server_id = :sid"]
+        params: dict = {"sid": server_id, "limit": limit, "offset": offset}
+        if search:
+            conditions.append("name LIKE :search")
+            params["search"] = f"%{search}%"
+        where = " AND ".join(conditions)
+        total_row = self._fetchone(
+            f"SELECT COUNT(*) as cnt FROM player_history WHERE {where}", params
+        )
+        total = total_row["cnt"] if total_row else 0
+        rows = self._fetchall(
+            f"SELECT * FROM player_history WHERE {where} ORDER BY left_at DESC LIMIT :limit OFFSET :offset",
+            params,
+        )
+        return total, rows