Fix: Simplify integration and fix admin template

- Removed settings/navigation from appinfo/info.xml
  - These sections can cause routing conflicts
  - App now relies purely on routes.php
- Simplified Application.php
  - Removed manual service/controller registration
  - Let Nextcloud DI framework handle it automatically
- Fixed admin template to use Nextcloud standards
  - Removed non-standard style() call
  - Added proper l10n support with p($l->t(...))
  - Clean template structure
- Created css/admin.css
  - Nextcloud-compatible styling
  - Matches design language
- Created js/admin.js
  - Handles Save Configuration button
  - Handles Test Connection button
  - Uses OC, OC.Notification APIs

This should fix admin page not appearing issue.
Users can access via: Settings → Administration → Additional Settings

analyticshub/js/admin.js

@@ -0,0 +1,66 @@
+(function() {
+    'use strict';
+
+    const saveButton = document.getElementById('analytics-hub-save');
+    const testButton = document.getElementById('analytics-hub-test');
+
+    if (saveButton) {
+        saveButton.addEventListener('click', function() {
+            // Collect form data
+            const data = {
+                google_client_id: document.getElementById('google_client_id').value,
+                google_client_secret: document.getElementById('google_client_secret').value,
+                google_refresh_token: document.getElementById('google_refresh_token').value,
+                anthropic_api_key: document.getElementById('anthropic_api_key').value
+            };
+
+            // Send save request
+            fetch(OC.generateUrl('/apps/analyticshub/admin/save'), {
+                method: 'POST',
+                headers: {
+                    'Content-Type': 'application/json',
+                    'requesttoken': OC.requestToken
+                },
+                body: JSON.stringify(data)
+            })
+            .then(response => response.json())
+            .then(data => {
+                if (data.success) {
+                    OC.Notification.showTemporary(t('analyticshub', 'Configuration saved successfully'));
+                } else {
+                    OC.Notification.showTemporary(t('analyticshub', 'Error: ' + data.error));
+                }
+            })
+            .catch(error => {
+                OC.Notification.showTemporary(t('analyticshub', 'Error saving configuration'));
+            });
+        });
+    }
+
+    if (testButton) {
+        testButton.addEventListener('click', function() {
+            // Test connections
+            fetch(OC.generateUrl('/apps/analyticshub/admin/status'), {
+                method: 'GET',
+                headers: {
+                    'requesttoken': OC.requestToken
+                }
+            })
+            .then(response => response.json())
+            .then(data => {
+                if (data.success) {
+                    const status = data.data;
+                    const message = [
+                        'App Status: ' + status.status,
+                        'Google Analytics: ' + status.google_analytics,
+                        'LLM Service: ' + status.llm_service
+                    ].join('\n');
+                    alert(message);
+                }
+            })
+            .catch(error => {
+                OC.Notification.showTemporary(t('analyticshub', 'Error getting status'));
+            });
+        });
+    }
+})();