fix(sessions): keep missing-worktree relocation manual

Remove automatic moves on session activation, terminal failures, and archive restoration while preserving manual moves and worktree deletion.

Replace directory listing probes with a stat-only endpoint using Node built-ins, including an isolated module-load regression test for packaged desktop.

Validation: focused session, worktree, filesystem, localization, and bridge tests; workspace type-check and lint; web and VS Code builds. Desktop startup and behavior verified by the maintainer.

packages/vscode/src/bridge-localfs-proxy-runtime.ts

@@ -56,6 +56,9 @@ export const tryHandleLocalFsProxy = async (method: string, requestPath: string)
   }
 
   const fsProxyPath = normalizeFsProxyPath(parsed.pathname);
+  if (parsed.pathname === '/api/fs/directory-stat') {
+    return buildProxyJsonError(501, 'Directory availability probes are not supported in the VS Code runtime');
+  }
   if (/^\/api\/openchamber\/sessions\/[^/]+\/markdown-image-grants$/.test(parsed.pathname)) {
     return buildProxyJsonError(501, 'Markdown image grants are not supported in the VS Code runtime');
   }