Home button fits all of Slovakia; add an overview map, top-right

Home now fitBounds()s a country-wide bbox instead of resetting to
CENTER/ZOOM's Bratislava point, since Home resetting into the same
city you'd already be looking at wasn't useful.

The overview map is NPS's own overview plugin (npmap5-plugins, still
on an unmerged branch), vendored and converted from its UMD dist
build to a plain ES module. Patched one MapLibre API break found while
verifying it: the plugin reads map.transform (public in the MapLibre
~2.4 it targets) to relax the inset's polar pan limit; MapLibre 6 (this
app's vendored version) no longer exposes .transform at all, so it
threw on load. Guarded to skip that cosmetic adjustment when absent
instead.

docs/third-party-notices.adoc

@@ -36,8 +36,21 @@ required):
 | NPS Home Button (`home-button`)
 | 0.0.1-d
 | https://github.com/nationalparkservice/npmap5-plugins/tree/main/home-button
+
+| NPS Overview Map (`maplibre-gl-overview`)
+| 5.0.1
+| https://github.com/nationalparkservice/npmap5-plugins/tree/maplibre-gl-overview
 |===
 
+The overview map is vendored from an unmerged branch, not `main` (see
+`docs/nps-resources.adoc`), and converted from its UMD dist build to a
+plain ES module — no functional change except the module wrapper. It
+was also patched for a MapLibre API break: it reads `map.transform`
+(public in the MapLibre ~2.4 this plugin targets) to relax the
+overview's polar pan limit, but MapLibre 6's `Map` no longer exposes
+`.transform` at all — guarded to skip that (cosmetic) adjustment
+instead of throwing when it's absent.
+
 Offline map text labels need font glyphs too (see
 `docs/architecture.adoc`), vendored under `public/vendor/fonts/` —
 SIL Open Font License, not BSD-3-Clause like the above: