core: change db keys to include collection name

This should not affect the items or their server representation.
This change is necessary to allow multiple items with same id
that live in different collections.
For example, shortcuts have the same id as the inner reference they
point to. This was not possible before and would cause an overwrite
of the original value.

packages/core/database/storage.js

@@ -20,8 +20,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 import { randomBytes } from "../utils/random";
 
 export default class Storage {
-  constructor(context) {
-    this.storage = context;
+  constructor(storage) {
+    this.storage = storage;
   }
 
   write(key, data) {