feat(nav): surface AP Groups page; always-fresh device data on edit pages

The AP Groups page (ApGroups.vue + ApGroupController + UnifiApiClient
CRUD methods) has been built but never declared in composer.json's
pages list, so it was hidden from the menu. Added it at sort_order=6,
between WiFi Networks and Portal.

The WiFi Networks page already has per-SSID AP-group assignment via
the existing updateApGroups route — that wires into UniFi's standard
ap_group_ids field on wlanconf. (UniFi doesn't expose per-AP-only
assignment separately; the convention is "make a one-AP group for
this AP and assign the SSID to it.")

For the "always pull from UniFi on load" guarantee:
- getWlans() and getApGroups() are already uncached — fresh on every
  page load
- getDevices() (feeds the AP picker for group membership) is cached
  for unifi.cache_ttl seconds; both ApGroupController::index and
  WifiController::index now Cache::forget('unifi:devices') before
  reading so the device list is always fresh

v1.3.0.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/Http/Controllers/WifiController.php

@@ -13,6 +13,11 @@ class WifiController extends Controller
 {
     public function index(UnifiApiClient $unifi)
     {
+        // Always pull fresh device data on this page so AP-group / SSID
+        // edits never go out against a stale snapshot. getWlans() and
+        // getApGroups() aren't cached, but getDevices() is.
+        \Illuminate\Support\Facades\Cache::forget('unifi:devices');
+
         try {
             $wlans = collect($unifi->getWlans())->map(fn ($w) => $this->mapWlan($w))->values();