feat: per-position camera settings, material alias dialog, product delete, media browser links

- Per-render-position focal_length_mm/sensor_width_mm (DB → pipeline → Blender)
- FOV-based camera distance with min clamp fix for wide-angle lenses
- Unmapped materials blocking dialog on "Dispatch Renders" with batch alias creation
- Material check endpoint (GET /orders/{id}/check-materials)
- Batch alias endpoint (POST /materials/batch-aliases)
- Quick-map "No alias" badges on Materials page
- Full product hard-delete with storage cleanup (MinIO + disk files + orphaned CadFile)
- Delete button on ProductDetail page with confirmation
- Clickable product names in Media Browser (links to product page)
- Single-line render dispatch/retry (POST /orders/{id}/lines/{id}/dispatch-render)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/app/api/routers/products.py

@@ -270,12 +270,73 @@ async def delete_product(
         raise HTTPException(404, detail="Product not found")
     if hard:
         from sqlalchemy import delete as sql_delete
-        # Delete order_lines referencing this product
+        from app.domains.media.models import MediaAsset
+        from app.core.storage import get_storage
+
+        # 1. Collect storage keys from MediaAssets before cascade deletes them
+        media_result = await db.execute(
+            select(MediaAsset.storage_key).where(MediaAsset.product_id == product_id)
+        )
+        storage_keys = [row[0] for row in media_result.all() if row[0]]
+
+        # 2. Collect render result paths from order lines
+        ol_result = await db.execute(
+            select(OrderLine.result_path).where(
+                OrderLine.product_id == product_id,
+                OrderLine.result_path.isnot(None),
+            )
+        )
+        result_paths = [row[0] for row in ol_result.all() if row[0]]
+
+        # 3. Check if CadFile is used by other products
+        cad_file_id = product.cad_file_id
+        orphan_cad = False
+        if cad_file_id:
+            other_count = await db.execute(
+                select(func.count(Product.id)).where(
+                    Product.cad_file_id == cad_file_id,
+                    Product.id != product_id,
+                )
+            )
+            orphan_cad = (other_count.scalar() or 0) == 0
+
+        # 4. Delete order_lines referencing this product
         await db.execute(sql_delete(OrderLine).where(OrderLine.product_id == product_id))
+
+        # 5. Delete orphaned CadFile if no other products reference it
+        if orphan_cad and cad_file_id:
+            from app.models.cad_file import CadFile
+            # Collect CadFile media assets too
+            cad_media_result = await db.execute(
+                select(MediaAsset.storage_key).where(MediaAsset.cad_file_id == cad_file_id)
+            )
+            storage_keys.extend(row[0] for row in cad_media_result.all() if row[0])
+            product.cad_file_id = None
+            await db.flush()
+            await db.execute(sql_delete(CadFile).where(CadFile.id == cad_file_id))
+
+        # 6. Delete product (cascades MediaAsset + ProductRenderPosition)
         await db.delete(product)
+        await db.commit()
+
+        # 7. Clean up storage files (best-effort, after commit)
+        storage = get_storage()
+        for key in storage_keys:
+            try:
+                storage.delete(key)
+            except Exception:
+                pass
+        # Clean up render result files on disk
+        import os
+        for path in result_paths:
+            try:
+                if os.path.isfile(path):
+                    os.unlink(path)
+            except Exception:
+                pass
     else:
         product.is_active = False
-    await db.commit()
+        await db.commit()
 
 
 @router.post("/{product_id}/cad", status_code=status.HTTP_201_CREATED)