feat: update for Nextcloud 33 and refactor Talk integration

Channel list working, url generation, just need posting working now

- Update dependency to Nextcloud 33 and add `spreed` dependency
- Change webhook route from `/webhook` to `/bot-webhook`
- Add `NavigationProvider` to add app to admin settings menu
- Refactor `TalkService` to query Talk DB directly for room listing (public channels)
- Update `postToRoom` to use Talk Chat API with Basic Auth for `talk-bot` user
- Add debug helper methods to `TalkService` for room debugging
- Enhance `debug` endpoint with detailed system and Talk configuration info
- Update admin settings UI with "Default Sender Name" field and improved room selection
- Add localization strings to admin settings
- Update documentation (`INSTALL.md`, `README.md`) for new route and bot admin requirement
- Improve `getBaseUrl` logic to prioritize `trusted_domains` for Docker compatibility

lib/NavigationProvider.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace OCA\NCdiscordhook;
+
+use OCP\IConfig;
+use OCP\IL10N;
+use OCP\IURLGenerator;
+use OCP\IUserSession;
+use OCP\Navigation\INavigationProvider;
+
+class NavigationProvider implements INavigationProvider {
+    public function __construct(
+        private readonly IURLGenerator $urlGenerator,
+        private readonly IUserSession $userSession,
+        private readonly IConfig $config,
+        private readonly IL10N $l10n,
+    ) {}
+
+    public function getNavigation(): array {
+        $user = $this->userSession->getUser();
+        if ($user === null || !$user->isAdmin()) {
+            return [];
+        }
+
+        return [
+            [
+                'id' => 'ncdiscordhook',
+                'app_id' => 'ncdiscordhook',
+                'type' => 'settings',
+                'name' => $this->l10n->t('NCdiscordhook'),
+                'href' => $this->urlGenerator->linkToRoute('settings.AdminSettings#index'),
+                'icon' => $this->urlGenerator->imagePath('ncdiscordhook', 'app.svg'),
+                'order' => 0,
+            ],
+        ];
+    }
+}