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/dependencies.py

@@ -0,0 +1,86 @@
+"""Reusable FastAPI dependencies."""
+from __future__ import annotations
+
+import logging
+from typing import Annotated
+
+from fastapi import Depends, Header, HTTPException, status
+from fastapi.security import HTTPAuthorizationCredentials, HTTPBearer
+from jose import JWTError
+from sqlalchemy.engine import Connection
+
+from core.auth.utils import decode_access_token
+from database import get_db
+
+logger = logging.getLogger(__name__)
+_security = HTTPBearer()
+
+
+def get_current_user(
+    credentials: Annotated[HTTPAuthorizationCredentials, Depends(_security)],
+    db: Annotated[Connection, Depends(get_db)],
+) -> dict:
+    """Decode JWT and return user dict. Raises 401 on any failure."""
+    token = credentials.credentials
+    try:
+        payload = decode_access_token(token)
+    except JWTError as e:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail={"code": "UNAUTHORIZED", "message": "Invalid or expired token"},
+        )
+    # Optionally verify user still exists in DB
+    from core.dal.base_repository import BaseRepository
+    from sqlalchemy import text
+    row = db.execute(
+        text("SELECT id, username, role FROM users WHERE id = :id"),
+        {"id": int(payload["sub"])},
+    ).fetchone()
+    if row is None:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail={"code": "UNAUTHORIZED", "message": "User not found"},
+        )
+    return dict(row._mapping)
+
+
+def require_admin(
+    user: Annotated[dict, Depends(get_current_user)],
+) -> dict:
+    """Raise 403 if user is not admin."""
+    if user["role"] != "admin":
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail={"code": "FORBIDDEN", "message": "Admin role required"},
+        )
+    return user
+
+
+def get_server_or_404(server_id: int, db: Connection) -> dict:
+    """Load server by ID or raise 404."""
+    from sqlalchemy import text
+    row = db.execute(
+        text("SELECT * FROM servers WHERE id = :id"), {"id": server_id}
+    ).fetchone()
+    if row is None:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail={"code": "NOT_FOUND", "message": f"Server {server_id} not found"},
+        )
+    return dict(row._mapping)
+
+
+def get_adapter_for_server(server_id: int, db: Connection):
+    """Load server and resolve its adapter. Raises 404 if server not found."""
+    server = get_server_or_404(server_id, db)
+    from adapters.registry import GameAdapterRegistry
+    try:
+        return GameAdapterRegistry.get(server["game_type"])
+    except KeyError:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail={
+                "code": "GAME_TYPE_NOT_FOUND",
+                "message": f"No adapter for game type '{server['game_type']}'",
+            },
+        )