fix: profile import file upload, startup health check, sidebar scroll, node-pty fallback

- Change profile import from server path input to browser file upload (multipart)
- Fix startup script to wait for health check before opening browser
- Add overflow scroll with hidden scrollbar to sidebar nav
- Graceful degradation when node-pty fails to load (WSL compatibility)
- Remove rename button from profile cards
- Restrict profile name input to English letters, numbers, hyphens
- Use raw.githubusercontent.com URLs in README setup script

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/client/src/i18n/locales/en.ts

@@ -232,8 +232,10 @@ export default {
     exportFailed: 'Failed to export profile',
     importSuccess: 'Profile imported',
     importFailed: 'Failed to import profile',
+    importSelectFile: 'Select archive file',
+    importInvalidFile: 'Please select a valid archive (.tar.gz, .tgz, .gz, .zip)',
     name: 'Profile Name',
-    namePlaceholder: 'Enter profile name',
+    namePlaceholder: 'English letters, numbers, hyphens only',
     newName: 'New Name',
     newNamePlaceholder: 'Enter new name',
     cloneFromCurrent: 'Clone from current profile',