Implement Baishi undelivered-data extraction and restructure menu by site

- Replace Baishi placeholders with full download flow (scan-rate query, export modal, password auth via config.yaml)
- Reorganize router menu into 顺心 / 百世 modules; move undelivered-data compare into 顺心 flow
- Add config.example.yaml and ignore config.yaml to keep credentials out of VCS

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

.gitignore

@@ -48,6 +48,9 @@ downloads/
 .env
 .env.local
 
+# Local secrets / credentials
+config.yaml
+
 # Playwright
 .playwright/
 ms-playwright/