Initial commit: AudiOhm - Alternative Spotify avec streaming YouTube

Backend:
- FastAPI avec PostgreSQL et Redis
- Authentification JWT complète
- API REST pour musique, playlists, recherche
- Streaming audio via yt-dlp
- SQLAlchemy 2.0 async

Frontend:
- Flutter avec thème néon cyberpunk
- State management Riverpod
- Layout adaptatif desktop/mobile
- Lecteur audio avec mini-player

Infrastructure:
- Docker Compose (PostgreSQL + Redis)
- Scripts d'installation automatisés
- Scripts de build pour exécutables

Fichiers ajoutés:
- BUILD_CLIENT_*.bat/sh: Scripts de compilation
- BUILD_CLIENT_README.md: Documentation compilation
- CHECK_FLUTTER.sh: Vérificateur d'environnement
- requirements.txt mis à jour pour Python 3.13
- Modèles SQLAlchemy corrigés (metadata -> extra_metadata)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

backend/app/schemas/auth.py

@@ -0,0 +1,71 @@
+"""Authentication schemas."""
+from datetime import datetime
+from typing import Optional
+
+from pydantic import BaseModel, EmailStr, Field, ConfigDict
+
+
+class UserBase(BaseModel):
+    """Base user schema."""
+
+    email: EmailStr
+    username: str = Field(..., min_length=3, max_length=50)
+    display_name: Optional[str] = Field(None, max_length=100)
+
+
+class UserCreate(UserBase):
+    """Schema for creating a new user."""
+
+    password: str = Field(..., min_length=8, max_length=100)
+
+
+class UserUpdate(BaseModel):
+    """Schema for updating user profile."""
+
+    display_name: Optional[str] = Field(None, max_length=100)
+    avatar_url: Optional[str] = None
+    date_of_birth: Optional[datetime] = None
+    country: Optional[str] = Field(None, max_length=2)
+
+
+class UserResponse(UserBase):
+    """Schema for user response."""
+
+    model_config = ConfigDict(from_attributes=True)
+
+    id: str
+    display_name: Optional[str] = None
+    avatar_url: Optional[str] = None
+    is_premium: bool = False
+    created_at: datetime
+    updated_at: datetime
+
+
+class Token(BaseModel):
+    """Schema for JWT token response."""
+
+    access_token: str
+    refresh_token: str
+    token_type: str = "bearer"
+    expires_in: int  # seconds
+
+
+class TokenPayload(BaseModel):
+    """Schema for JWT token payload."""
+
+    sub: str  # user id
+    exp: int  # expiration timestamp
+    type: str  # "access" or "refresh"
+
+
+class LoginRequest(BaseModel):
+    """Schema for login request."""
+
+    email: EmailStr
+    password: str
+
+
+class RefreshTokenRequest(BaseModel):
+    """Schema for token refresh request."""
+
+    refresh_token: str