Polish the Site and Facility settings page

Booleans render as checkbox toggles, the employee/USB directory-mode
settings as selfhosted/external dropdowns, and every field has a label
and help text (raw keys and type-true/false text boxes are gone).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

CHANGELOG.md

@@ -94,6 +94,9 @@ ADR-007 and ADR-002.
 
 ### Fixed
 
+- Site & Facility settings page renders booleans as toggles and the
+  directory-mode settings as dropdowns, with labels and help text for every
+  field (no more raw keys or type-true/false boxes).
 - System Settings tabs follow the URL: clicking a settings-rail link that
   only changes the ?tab= query (Branding, Floor Map) now switches the right
   panel, tab clicks update the URL, and browser back/forward restore tabs.