feat: enhance webhook settings UI and security: Mostly working, just final post not functioning

- Add CSS styles for token URL input and hints
- Implement safe data attribute parsing in settings.js
- Refactor room fetching logic to use promise chains and auto-fetch on load
- Display full webhook URLs in the settings UI instead of raw tokens
- Generate URL-safe base64 tokens to prevent encoding issues
- Add #[PublicPage] attribute to WebhookController for unauthenticated delivery
- Filter out internal Nextcloud Talk system rooms from the room picker
- Add OCS-ApiRequest header to bot API requests
- Sanitize data attributes in templates to prevent XSS

css/adminSettings.css

@@ -37,6 +37,23 @@
     padding: 4px 8px;
     border-radius: 3px;
 }
+.nc-token-url-input {
+    flex: 1;
+    font-family: monospace;
+    font-size: 0.8em;
+    background: var(--color-main-background);
+    border: 1px solid var(--color-border);
+    padding: 4px 8px;
+    border-radius: 3px;
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+}
+.nc-token-hint {
+    color: var(--color-text-lighter);
+    font-size: 0.85em;
+    margin: 4px 0;
+}
 .nc-token-copy {
     padding: 4px 8px;
     background: var(--color-primary-element);