Reduce deprecated API and dependency warnings

src/common/compatibilitySettings.ts

@@ -0,0 +1,32 @@
+type LegacyLocalDatabaseSelection = {
+    useIndexedDBAdapter: boolean;
+};
+
+type LegacyBulkChunkPreSendSettings = {
+    sendChunksBulk: boolean;
+    sendChunksBulkMaxSize: number;
+};
+
+/**
+ * Returns whether persisted settings select the legacy PouchDB IndexedDB adapter.
+ *
+ * New local databases use IDB. Existing devices must retain this operative value until their local database has
+ * been explicitly migrated, so compatibility code must not treat the setting as inert.
+ */
+export function usesLegacyIndexedDBAdapter(settings: LegacyLocalDatabaseSelection): boolean {
+    return settings.useIndexedDBAdapter;
+}
+
+/**
+ * Disables the removed automatic bulk chunk pre-send option in persisted settings.
+ *
+ * The field remains readable only so older settings and Setup URIs can be migrated to the supported behaviour.
+ *
+ * @returns `true` when the legacy setting was enabled and has been changed.
+ */
+export function disableLegacyBulkChunkPreSend(settings: LegacyBulkChunkPreSendSettings): boolean {
+    if (!settings.sendChunksBulk) return false;
+    settings.sendChunksBulk = false;
+    settings.sendChunksBulkMaxSize = 1;
+    return true;
+}