feat: add troubleshooting settings with open app data and reset workspace

Add a Troubleshooting section under a Support nav group in Settings:

- Open App Data Folder: reveals the user-data directory in the OS file
  explorer via shell.openPath.
- Reset Local Workspace: destructive action that deletes workspace.json
  and scratchpad contents, clears the in-memory cache, and reseeds
  defaults. Auth secrets are preserved. Requires two-step confirmation.

New IPC channels, ElectronApi methods, and preload bridge added for
openAppDataFolder and resetLocalWorkspace. Existing electron mock in
tests updated to include shell.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/main/EryxAppService.ts

@@ -1,7 +1,8 @@
 import { EventEmitter } from 'node:events';
-import { basename } from 'node:path';
+import { rm } from 'node:fs/promises';
+import { basename, dirname } from 'node:path';
 
-import { dialog } from 'electron';
+import { dialog, shell } from 'electron';
 
 import type {
   AgentActivityEvent,
@@ -159,6 +160,28 @@ export class EryxAppService extends EventEmitter<AppServiceEvents> {
     void this.secretStore;
   }
 
+  async openAppDataFolder(): Promise<void> {
+    const appDataPath = dirname(this.workspaceRepository.filePath);
+    await shell.openPath(appDataPath);
+  }
+
+  async resetLocalWorkspace(): Promise<WorkspaceState> {
+    await this.sidecar.dispose();
+
+    try {
+      await rm(this.workspaceRepository.filePath, { force: true });
+      await rm(this.workspaceRepository.scratchpadPath, { recursive: true, force: true });
+    } catch (error) {
+      console.error('[aryx reset]', error);
+    }
+
+    this.workspace = undefined;
+    this.sidecarCapabilities = undefined;
+    this.didScheduleInitialProjectGitRefresh = false;
+
+    return this.loadWorkspace();
+  }
+
   async addProject(): Promise<WorkspaceState> {
     const workspace = await this.loadWorkspace();
     const result = await dialog.showOpenDialog({

src/main/ipc/registerIpcHandlers.ts

@@ -96,6 +96,8 @@ export function registerIpcHandlers(window: BrowserWindow, service: EryxAppServi
   ipcMain.handle(ipcChannels.selectProject, (_event, projectId?: string) => service.selectProject(projectId));
   ipcMain.handle(ipcChannels.selectPattern, (_event, patternId?: string) => service.selectPattern(patternId));
   ipcMain.handle(ipcChannels.selectSession, (_event, sessionId?: string) => service.selectSession(sessionId));
+  ipcMain.handle(ipcChannels.openAppDataFolder, () => service.openAppDataFolder());
+  ipcMain.handle(ipcChannels.resetLocalWorkspace, () => service.resetLocalWorkspace());
 
   service.on('workspace-updated', (workspace) => {
     window.webContents.send(ipcChannels.workspaceUpdated, workspace);