feat: consolidate media service, add merchant users page, fix metrics overlap

- Merge ImageService into MediaService with WebP variant generation,
  DB-backed storage stats, and module-driven media usage discovery
  via new MediaUsageProviderProtocol
- Add merchant users admin page with scoped user listing, stats
  endpoint, template, JS, and i18n strings (de/en/fr/lb)
- Fix merchant user metrics so Owners and Team Members are mutually
  exclusive (filter team_members on user_type="member" and exclude
  owner IDs) ensuring stat cards add up correctly
- Update billing and monitoring services to use media_service
- Update subscription-billing and feature-gating docs

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

app/modules/cms/routes/api/admin_images.py

@@ -3,97 +3,33 @@
 Admin image management endpoints.
 
 Provides:
-- Image upload with automatic processing
-- Image deletion
-- Storage statistics
+- Storage statistics (delegates to MediaService)
 """
 
 import logging
 
-from fastapi import APIRouter, Depends, File, Form, UploadFile
+from fastapi import APIRouter, Depends
+from sqlalchemy.orm import Session
 
 from app.api.deps import get_current_admin_api
-from app.modules.core.services.image_service import image_service
+from app.core.database import get_db
+from app.modules.cms.services.media_service import media_service
 from models.schema.auth import UserContext
-from app.modules.cms.schemas.image import (
-    ImageDeleteResponse,
-    ImageStorageStats,
-    ImageUploadResponse,
-)
+from app.modules.cms.schemas.image import ImageStorageStats
 
 admin_images_router = APIRouter(prefix="/images")
 logger = logging.getLogger(__name__)
 
 
-@admin_images_router.post("/upload", response_model=ImageUploadResponse)
-async def upload_image(
-    file: UploadFile = File(...),
-    store_id: int = Form(...),
-    product_id: int | None = Form(None),
-    current_admin: UserContext = Depends(get_current_admin_api),
-):
-    """Upload and process an image.
-
-    The image will be:
-    - Converted to WebP format
-    - Resized to multiple variants (original, 800px, 200px)
-    - Stored in a sharded directory structure
-
-    Args:
-        file: Image file to upload
-        store_id: Store ID for the image
-        product_id: Optional product ID
-
-    Returns:
-        Image URLs and metadata
-    """
-    # Read file content
-    content = await file.read()
-
-    # Delegate all validation and processing to service
-    result = image_service.upload_product_image(
-        file_content=content,
-        filename=file.filename or "image.jpg",
-        content_type=file.content_type,
-        store_id=store_id,
-        product_id=product_id,
-    )
-
-    logger.info(f"Image uploaded: {result['id']} for store {store_id}")
-
-    return ImageUploadResponse(success=True, image=result)
-
-
-@admin_images_router.delete("/{image_hash}", response_model=ImageDeleteResponse)
-async def delete_image(
-    image_hash: str,
-    current_admin: UserContext = Depends(get_current_admin_api),
-):
-    """Delete an image and all its variants.
-
-    Args:
-        image_hash: The image ID/hash
-
-    Returns:
-        Deletion status
-    """
-    deleted = image_service.delete_product_image(image_hash)
-
-    if deleted:
-        logger.info(f"Image deleted: {image_hash}")
-        return ImageDeleteResponse(success=True, message="Image deleted successfully")
-    else:
-        return ImageDeleteResponse(success=False, message="Image not found")
-
-
 @admin_images_router.get("/stats", response_model=ImageStorageStats)
 async def get_storage_stats(
     current_admin: UserContext = Depends(get_current_admin_api),
+    db: Session = Depends(get_db),
 ):
     """Get image storage statistics.
 
     Returns:
         Storage metrics including file counts, sizes, and directory info
     """
-    stats = image_service.get_storage_stats()
+    stats = media_service.get_storage_stats(db)
     return ImageStorageStats(**stats)

app/modules/cms/routes/api/store_media.py

@@ -257,17 +257,29 @@ def get_media_usage(
     """
     Get where this media file is being used.
 
-    - Check products using this media
-    - Return list of usage
+    Discovers usage from all registered module providers.
     """
-    # Service will raise MediaNotFoundException if not found
-    usage = media_service.get_media_usage(
+    # Verify media belongs to store (raises MediaNotFoundException if not found)
+    media_service.get_media(
         db=db,
         store_id=current_user.token_store_id,
         media_id=media_id,
     )
 
-    return MediaUsageResponse(**usage)
+    # Discover usage from registered providers
+    from app.modules.registry import MODULES
+
+    usage = []
+    for module in MODULES.values():
+        provider = module.get_media_usage_provider_instance()
+        if provider:
+            usage.extend(provider.get_media_usage(db, media_id))
+
+    return MediaUsageResponse(
+        media_id=media_id,
+        usage=usage,
+        total_usage_count=len(usage),
+    )
 
 
 @store_media_router.post("/optimize/{media_id}", response_model=OptimizationResultResponse)