fix(crawler): guard headless nav against internal SSRF targets on list/detail path

`navigate()` (list/detail/pagination) and the session probe called
`Browser::new_page()` without the SSRF check that already guards the
chapter-content path, so a hostile or compromised scraped source could
serve `<a href="http://169.254.169.254/…">` / `http://postgres:5432/` in a
listing and use the in-container Chromium as a read oracle.

Add `guard_navigate_url` (reusing `ensure_public_target`) at the top of
`navigate`, before rate-limiting or opening a page, and apply the same
check to `fetch_probe_html`. Covers base URL, pagination, and detail links.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "mangalord-frontend",
-  "version": "0.93.2",
+  "version": "0.93.3",
   "private": true,
   "type": "module",
   "scripts": {