ADFA-5094: single source of truth for the catalog overlay basename

Review follow-up: BundledCatalogSource.ASSET and CatalogRepositoryImpl.BASENAME both
held "kolibri_catalog.jsonl" independently, so the source (reads the overlay) and the
worker (writes it) could silently drift. BASENAME now references ASSET.

Author: luisguzman-adfa

controller/app/src/main/java/org/iiab/controller/kolibri/data/BundledCatalogSource.java

@@ -45,7 +45,9 @@
 public final class BundledCatalogSource {
 
     private static final String TAG = "K2Go-Kolibri";
-    private static final String ASSET = "kolibri_catalog.jsonl";
+    // ADFA-5094: also the overlay basename — CatalogRepositoryImpl points the refresh worker at
+    // this same name, so the worker writes the overlay exactly where this source looks for it.
+    static final String ASSET = "kolibri_catalog.jsonl";
 
     /** Marks the header line, so it is never mistaken for a channel. */
     private static final String HEADER_KEY = "catalog";

controller/app/src/main/java/org/iiab/controller/kolibri/data/CatalogRepositoryImpl.java

@@ -33,7 +33,9 @@ public final class CatalogRepositoryImpl implements CatalogRepository {
     private static final String CATALOG = "kolibri";
     private static final String MANIFEST_URL =
             "https://k2go-download.appdevforall.org/catalogs/kolibri.manifest.json";
-    private static final String BASENAME = "kolibri_catalog.jsonl";
+    // Single source of truth for the basename: the same name BundledCatalogSource reads the overlay
+    // from, so the worker writes it exactly where the source looks (they must never drift).
+    private static final String BASENAME = BundledCatalogSource.ASSET;
 
     private final BundledCatalogSource bundled;
     private final StudioTreeSource studio;