fix: provide valid mock config to fix GUI test failures

The added `!configResult.config` guard in ParallelListeners caused tests
to bail early since MockIdeMessenger returned `config: undefined`.

Author: RomneyDa

gui/src/context/MockIdeMessenger.ts

@@ -81,7 +81,34 @@ const DEFAULT_MOCK_CORE_RESPONSES: MockResponses = {
     ],
     profileId: "local",
     result: {
-      config: undefined,
+      config: {
+        tools: [],
+        slashCommands: [],
+        contextProviders: [],
+        mcpServerStatuses: [],
+        usePlatform: true,
+        modelsByRole: {
+          chat: [],
+          apply: [],
+          edit: [],
+          summarize: [],
+          autocomplete: [],
+          rerank: [],
+          embed: [],
+          subagent: [],
+        },
+        selectedModelByRole: {
+          chat: null,
+          apply: null,
+          edit: null,
+          summarize: null,
+          autocomplete: null,
+          rerank: null,
+          embed: null,
+          subagent: null,
+        },
+        rules: [],
+      },
       errors: [],
       configLoadInterrupted: false,
     },