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/servers/schemas.py

@@ -0,0 +1,35 @@
+from __future__ import annotations
+
+from pydantic import BaseModel, Field
+
+
+class CreateServerRequest(BaseModel):
+    name: str
+    description: str | None = None
+    game_type: str = "arma3"
+    exe_path: str
+    game_port: int = Field(ge=1024, le=65535)
+    rcon_port: int | None = Field(default=None, ge=1024, le=65535)
+    auto_restart: bool = False
+    max_restarts: int = Field(default=3, ge=0, le=20)
+
+
+class UpdateServerRequest(BaseModel):
+    name: str | None = None
+    description: str | None = None
+    exe_path: str | None = None
+    game_port: int | None = Field(default=None, ge=1024, le=65535)
+    rcon_port: int | None = Field(default=None, ge=1024, le=65535)
+    auto_restart: bool | None = None
+    max_restarts: int | None = None
+
+
+class StopServerRequest(BaseModel):
+    force: bool = False
+    reason: str | None = None
+
+
+class UpdateConfigSectionRequest(BaseModel):
+    config_version: int | None = None  # Required for optimistic locking on PUT
+    # All other fields come from the adapter's JSON Schema — passed through as-is
+    model_config = {"extra": "allow"}