Initial scaffold: FastAPI backend + Vue 3 frontend + Docker setup

Backend: config/db/security/logging core, SQLAlchemy models (Server,
Credential, UpdateJob, UpdateLog, AuditLog, User), services (winrm, ssh,
cau, audit, job_runner), REST API (auth, servers, updates, audit),
Socket.io WebSocket layer.
Frontend: Vue 3 + TS + Pinia + Tailwind, Views (Dashboard, Servers,
Updates, Audit, Login), axios + socket.io-client, nginx prod config.

backend/app/models/user.py

@@ -0,0 +1,27 @@
+"""User model - local admins or LDAP-mapped users."""
+
+from datetime import UTC, datetime
+
+from sqlalchemy import Boolean, DateTime, String
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.core.database import Base
+
+
+class User(Base):
+    __tablename__ = "users"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    username: Mapped[str] = mapped_column(String(255), unique=True, index=True)
+    email: Mapped[str | None] = mapped_column(String(255), nullable=True)
+    full_name: Mapped[str | None] = mapped_column(String(255), nullable=True)
+
+    password_hash: Mapped[str | None] = mapped_column(String(255), nullable=True)  # null = LDAP only
+    is_ldap: Mapped[bool] = mapped_column(Boolean, default=False)
+    is_admin: Mapped[bool] = mapped_column(Boolean, default=False)
+    is_active: Mapped[bool] = mapped_column(Boolean, default=True)
+
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), default=lambda: datetime.now(UTC)
+    )
+    last_login_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)