Fix effects router to use proper ownership model

- Upload: Create item_types entry to track user-effect relationship
- List: Query item_types for user's effects instead of scanning filesystem
- Delete: Remove ownership link, only delete files if orphaned (garbage collect)

This matches the ownership model used by recipes and media, where multiple
users can "own" the same cached content through item_types entries.

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

app/routers/effects.py

@@ -200,6 +200,15 @@ async def upload_effect(
     # Also store metadata in IPFS for discoverability
     meta_cid = ipfs_client.add_json(full_meta)
 
+    # Track ownership in item_types
+    import database
+    await database.save_item_metadata(
+        cid=cid,
+        actor_id=ctx.actor_id,
+        item_type="effect",
+        filename=file.filename,
+    )
+
     # Assign friendly name
     from ..services.naming_service import get_naming_service
     naming = get_naming_service()
@@ -314,31 +323,33 @@ async def list_effects(
     limit: int = 20,
     ctx: UserContext = Depends(require_auth),
 ):
-    """List uploaded effects with pagination."""
+    """List user's effects with pagination."""
+    import database
     effects_dir = get_effects_dir()
     effects = []
 
+    # Get user's effect CIDs from item_types
+    user_items = await database.get_user_items(ctx.actor_id, item_type="effect", limit=1000)
+    effect_cids = [item["cid"] for item in user_items]
+
     # Get naming service for friendly name lookup
     from ..services.naming_service import get_naming_service
     naming = get_naming_service()
 
-    if effects_dir.exists():
-        for effect_dir in effects_dir.iterdir():
-            if effect_dir.is_dir():
-                metadata_path = effect_dir / "metadata.json"
-                if metadata_path.exists():
-                    try:
-                        meta = json.loads(metadata_path.read_text())
-                        # Add friendly name if available
-                        cid = meta.get("cid")
-                        if cid:
-                            friendly = await naming.get_by_cid(ctx.actor_id, cid)
-                            if friendly:
-                                meta["friendly_name"] = friendly["friendly_name"]
-                                meta["base_name"] = friendly["base_name"]
-                        effects.append(meta)
-                    except json.JSONDecodeError:
-                        pass
+    for cid in effect_cids:
+        effect_dir = effects_dir / cid
+        metadata_path = effect_dir / "metadata.json"
+        if metadata_path.exists():
+            try:
+                meta = json.loads(metadata_path.read_text())
+                # Add friendly name if available
+                friendly = await naming.get_by_cid(ctx.actor_id, cid)
+                if friendly:
+                    meta["friendly_name"] = friendly["friendly_name"]
+                    meta["base_name"] = friendly["base_name"]
+                effects.append(meta)
+            except json.JSONDecodeError:
+                pass
 
     # Sort by upload time (newest first)
     effects.sort(key=lambda e: e.get("uploaded_at", ""), reverse=True)
@@ -412,25 +423,29 @@ async def delete_effect(
     cid: str,
     ctx: UserContext = Depends(require_auth),
 ):
-    """Delete an effect from local cache (IPFS content is immutable)."""
-    effects_dir = get_effects_dir()
-    effect_dir = effects_dir / cid
+    """Remove user's ownership link to an effect."""
+    import database
 
-    if not effect_dir.exists():
-        raise HTTPException(404, f"Effect {cid[:16]}... not found in local cache")
+    # Remove user's ownership link from item_types
+    await database.delete_item_type(cid, ctx.actor_id, "effect")
 
-    # Check ownership
-    metadata_path = effect_dir / "metadata.json"
-    if metadata_path.exists():
-        meta = json.loads(metadata_path.read_text())
-        if meta.get("uploader") != ctx.actor_id:
-            raise HTTPException(403, "Can only delete your own effects")
+    # Remove friendly name
+    await database.delete_friendly_name(ctx.actor_id, cid)
 
-    import shutil
-    shutil.rmtree(effect_dir)
+    # Check if anyone still owns this effect
+    remaining_owners = await database.get_item_types(cid)
 
-    # Unpin from IPFS (content remains available if pinned elsewhere)
-    ipfs_client.unpin(cid)
+    # Only delete local files if no one owns it anymore
+    if not remaining_owners:
+        effects_dir = get_effects_dir()
+        effect_dir = effects_dir / cid
+        if effect_dir.exists():
+            import shutil
+            shutil.rmtree(effect_dir)
 
-    logger.info(f"Deleted effect {cid[:16]}... by {ctx.actor_id}")
-    return {"deleted": True, "note": "Unpinned from local IPFS; content may still exist on other nodes"}
+        # Unpin from IPFS
+        ipfs_client.unpin(cid)
+        logger.info(f"Garbage collected effect {cid[:16]}... (no remaining owners)")
+
+    logger.info(f"Removed effect {cid[:16]}... ownership for {ctx.actor_id}")
+    return {"deleted": True}