Add comprehensive test suite for image processing and related services

- Implement tests for database generator to ensure proper session handling.
- Create tests for EXIF extraction and conversion functions.
- Add tests for image-related endpoints, ensuring proper data retrieval and isolation between clients.
- Develop tests for OCR functionality, including language detection and text extraction.
- Introduce tests for the image processing pipeline, covering success and failure scenarios.
- Validate rate limiting functionality and ensure independent counters for different clients.
- Implement scraper tests to verify HTML content fetching and error handling.
- Add unit tests for various services, including storage and filename generation.
- Establish worker entry point for ARQ to handle background image processing tasks.

app/schemas/auth.py

@@ -0,0 +1,67 @@
+"""
+Schémas Pydantic — authentification et gestion des clients API
+"""
+from datetime import datetime
+from typing import List, Optional
+from pydantic import BaseModel, ConfigDict, Field
+from app.models.client import ClientPlan
+
+
+# ─────────────────────────────────────────────────────────────
+# Requêtes
+# ─────────────────────────────────────────────────────────────
+
+class ClientCreate(BaseModel):
+    """Créer un nouveau client API."""
+    name: str = Field(..., min_length=1, max_length=256, description="Nom de l'application cliente")
+    scopes: List[str] = Field(
+        default=["images:read", "images:write"],
+        description="Permissions accordées",
+    )
+    plan: ClientPlan = Field(default=ClientPlan.FREE, description="Plan tarifaire")
+
+
+class ClientUpdate(BaseModel):
+    """Modifier un client API existant."""
+    name: Optional[str] = Field(None, min_length=1, max_length=256)
+    scopes: Optional[List[str]] = None
+    plan: Optional[ClientPlan] = None
+    is_active: Optional[bool] = None
+
+
+# ─────────────────────────────────────────────────────────────
+# Réponses
+# ─────────────────────────────────────────────────────────────
+
+class ClientResponse(BaseModel):
+    """Réponse de base pour un client API."""
+    model_config = ConfigDict(from_attributes=True)
+
+    id: str
+    name: str
+    scopes: List[str]
+    plan: ClientPlan
+    is_active: bool
+    created_at: Optional[datetime] = None
+    updated_at: Optional[datetime] = None
+
+
+class ClientCreateResponse(ClientResponse):
+    """
+    Réponse après création d'un client.
+    La clé API est retournée EN CLAIR une seule fois.
+    """
+    api_key: str = Field(
+        ...,
+        description="Clé API en clair — stockez-la, elle ne sera plus jamais affichée",
+    )
+
+
+class KeyRotateResponse(BaseModel):
+    """Réponse après rotation de la clé API."""
+    id: str
+    api_key: str = Field(
+        ...,
+        description="Nouvelle clé API en clair — stockez-la, elle ne sera plus jamais affichée",
+    )
+    message: str = "Clé API régénérée avec succès — l'ancienne clé est désormais invalide"