Fix bookmarks menu dismiss, home Email URL, and deploy hygiene.

Close the hamburger panel on outside click/focus via X11 (xinput/xdotool)
without a fullscreen overlay; point home Email to Roundcube; sync
home-screen-index.html in deploy/install; remove credentials.md from git
and document private LAN-only Gitea usage.

Co-authored-by: Cursor <cursoragent@cursor.com>

credentials.md.example

@@ -0,0 +1,10 @@
+# Senior Kiosk — Credentials (template)
+
+> Copy to `credentials.md` (gitignored). Never commit real secrets.
+
+## Gmail App Password (for Roundcube IMAP)
+
+- **Account**: your-gmail@example.com
+- **Purpose**: Roundcube webmail IMAP/SMTP access
+- **App Password**: (create in Google Account → Security → App passwords)
+- **Note**: Configure on the Roundcube server only; do not commit to git.