Add materials, exam images, storage quota, and API guide

Upload documents for AI context, exam images for Moodle questions, per-template storage limits, embedded images in XML export, and GUIA_API_Y_FLUJO.md with full endpoint documentation.

backend/app/api/dependencies.py

@@ -6,11 +6,41 @@ from sqlalchemy.orm import Session
 from app.core.config import Settings, get_settings
 from app.db.session import get_db
 from app.services.exam_service import ExamService
+from app.services.image_service import ImageService
 from app.services.llm import LLMClient
+from app.services.material_service import MaterialService
+from app.services.storage_quota import StorageQuotaService
 
 
-def get_exam_service(db: Annotated[Session, Depends(get_db)]) -> ExamService:
-    return ExamService(db)
+def get_storage_quota_service(
+    db: Annotated[Session, Depends(get_db)],
+    settings: Annotated[Settings, Depends(get_settings)],
+) -> StorageQuotaService:
+    return StorageQuotaService(db, settings)
+
+
+def get_material_service(
+    db: Annotated[Session, Depends(get_db)],
+    settings: Annotated[Settings, Depends(get_settings)],
+    storage_quota: Annotated[StorageQuotaService, Depends(get_storage_quota_service)],
+) -> MaterialService:
+    return MaterialService(db, settings, storage_quota)
+
+
+def get_image_service(
+    db: Annotated[Session, Depends(get_db)],
+    settings: Annotated[Settings, Depends(get_settings)],
+    storage_quota: Annotated[StorageQuotaService, Depends(get_storage_quota_service)],
+) -> ImageService:
+    return ImageService(db, settings, storage_quota)
+
+
+def get_exam_service(
+    db: Annotated[Session, Depends(get_db)],
+    material_service: Annotated[MaterialService, Depends(get_material_service)],
+    image_service: Annotated[ImageService, Depends(get_image_service)],
+) -> ExamService:
+    return ExamService(db, material_service=material_service, image_service=image_service)
 
 
 def get_llm_client(settings: Annotated[Settings, Depends(get_settings)]) -> LLMClient: