feat(postgres): add extension management

apps/desktop/src/lib/backend/http.ts

@@ -715,7 +715,7 @@ export async function listOwners(connectionId: string, database: string, schema:
   return get(`/api/schema/owners?${qs({ connection_id: connectionId, database, schema })}`);
 }
 
-export async function listExtensions(connectionId: string, database: string, schema: string): Promise<ExtensionInfo[]> {
+export async function listExtensions(connectionId: string, database: string, schema?: string): Promise<ExtensionInfo[]> {
   return get(`/api/schema/extensions?${qs({ connection_id: connectionId, database, schema })}`);
 }
 

apps/desktop/src/lib/backend/tauri.ts

@@ -1201,7 +1201,7 @@ export async function listOwners(connectionId: string, database: string, schema:
   return invoke("list_owners", { connectionId, database, schema });
 }
 
-export async function listExtensions(connectionId: string, database: string, schema: string): Promise<ExtensionInfo[]> {
+export async function listExtensions(connectionId: string, database: string, schema?: string): Promise<ExtensionInfo[]> {
   return invoke("list_extensions", { connectionId, database, schema });
 }
 

apps/desktop/src/lib/sidebar/sidebarTreeItemLayout.ts

@@ -23,6 +23,7 @@ const leafTypes: Set<TreeNodeType> = new Set([
   "saved-sql-file",
   "table-search-control",
   "load-more",
+  "extension",
 ]);
 
 const fullWidthLabelTypes: Set<TreeNodeType> = new Set(["table", "view", "materialized_view", "mongo-collection", "mongo-bucket", "vector-collection", "elasticsearch-index"]);