feat: Space Booking System - MVP complet

Sistem web pentru rezervarea de birouri și săli de ședință
cu flux de aprobare administrativă.

Stack: FastAPI + Vue.js 3 + SQLite + TypeScript

Features implementate:
- Autentificare JWT + Self-registration cu email verification
- CRUD Spații, Utilizatori, Settings (Admin)
- Calendar interactiv (FullCalendar) cu drag-and-drop
- Creare rezervări cu validare (durată, program, overlap, max/zi)
- Rezervări recurente (săptămânal)
- Admin: aprobare/respingere/anulare cereri
- Admin: creare directă rezervări (bypass approval)
- Admin: editare orice rezervare
- User: editare/anulare rezervări proprii
- Notificări in-app (bell icon + dropdown)
- Notificări email (async SMTP cu BackgroundTasks)
- Jurnal acțiuni administrative (audit log)
- Rapoarte avansate (utilizare, top users, approval rate)
- Șabloane rezervări (booking templates)
- Atașamente fișiere (upload/download)
- Conflict warnings (verificare disponibilitate real-time)
- Integrare Google Calendar (OAuth2)
- Suport timezone (UTC storage + user preference)
- 225+ teste backend

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/core/config.py

@@ -0,0 +1,48 @@
+"""Application configuration."""
+from typing import List
+from pydantic_settings import BaseSettings, SettingsConfigDict
+
+
+class Settings(BaseSettings):
+    """Application settings."""
+
+    model_config = SettingsConfigDict(
+        env_file=".env",
+        env_file_encoding="utf-8",
+        case_sensitive=False
+    )
+
+    # App
+    app_name: str = "Space Booking API"
+    debug: bool = False
+
+    # Database
+    database_url: str = "sqlite:///./space_booking.db"
+
+    # JWT
+    secret_key: str = "your-secret-key-change-in-production"
+    algorithm: str = "HS256"
+    access_token_expire_minutes: int = 1440  # 24 hours
+
+    # SMTP
+    smtp_host: str = "localhost"
+    smtp_port: int = 1025  # MailHog default
+    smtp_user: str = ""
+    smtp_password: str = ""
+    smtp_from_address: str = "noreply@space-booking.local"
+    smtp_enabled: bool = False  # Disable by default for dev
+
+    # Frontend
+    frontend_url: str = "http://localhost:5173"
+
+    # Google Calendar OAuth
+    google_client_id: str = ""
+    google_client_secret: str = ""
+    google_redirect_uri: str = "http://localhost:8000/api/integrations/google/callback"
+    google_scopes: List[str] = [
+        "https://www.googleapis.com/auth/calendar",
+        "https://www.googleapis.com/auth/calendar.events"
+    ]
+
+
+settings = Settings()