docs: update documentation, add future tasks, and fix debug endpoint security

- **Documentation Overhaul**:
  - **README.md**: Restructured installation guide to align with Nextcloud 33+ paths (e.g., "Personal Settings → Security"), added curl examples, updated known limitations, and added a "Future Features" section.
  - **agent.md**: Updated architecture documentation to reflect `TalkService.php` growth (1138 to 1904 lines), updated constructor parameters, and corrected method documentation (e.g., `buildRichObject` now creates TYPE_ROOM shares, `postToRoom` uses query params).
  - **architecture.md**: Added notes regarding the admin gate for the debug endpoint.

- **New Files**:
  - Added `Future to-do.md` to track planned features (inbound messages, filtering, etc.).
  - Added `TODO.md` to track pending tasks and code cleanup.

- **Code Fixes**:
  - **lib/Controller/WebhookController.php**: Re-applied `#[AdminRequired]` attribute to the `debug()` method to enforce admin authentication.
  - **lib/Service/TalkService.php**: Updated docblock for `buildRichObject` to clarify it creates TYPE_ROOM shares.
  - **lib/Settings/Admin.php** & **templates/adminSettings.php**: Corrected bot password generation instructions to point to the correct Nextcloud settings path.

- **Configuration**:
  - **appinfo/info.xml**: Bumped version to 1.2.1 and updated `max-version` to 35.

lib/Controller/WebhookController.php

@@ -596,10 +596,12 @@ class WebhookController extends Controller {
      *
      * SECURITY: Never leave debug enabled in production. It exposes internal
      * configuration, database schema, and bot credentials.
+     *
+     * TODO: Add auto-disable timer (2-hour TTL) to prevent accidental prolonged exposure.
      */
     #[PublicPage]
     #[NoCSRFRequired]
-    #[NoAdminRequired]
+    #[AdminRequired]
     public function debug(): DataResponse {
         // Debug endpoint must be explicitly enabled via OCC command
         $debugEnabled = $this->appConfig->getValueBool('nc_bot_webhooks', 'debug_enabled', false);

lib/Service/TalkService.php

@@ -1077,7 +1077,9 @@ class TalkService {
 
     /**
      * Build rich object data for a Talk message from an uploaded file path.
-     * Creates a public link share so Talk can resolve the rich object.
+     * Creates a TYPE_ROOM share in the bot user's storage so Talk's SystemMessage
+     * parser can resolve the rich object inline. More secure than public link shares
+     * since the share is scoped to the room rather than publicly accessible.
      */
     public function buildRichObject(string $filePath, string $mimeType, string $roomToken): ?array {
         $this->logger->info('nc_bot_webhooks: buildRichObject ENTER', ['app' => self::APP_ID, 'filePath' => $filePath, 'roomToken' => $roomToken]);

lib/Settings/Admin.php

@@ -40,7 +40,7 @@ class Admin implements ISettings {
                 'no_rooms' => $this->l10n->t('No rooms found'),
                 'no_rooms_msg' => $this->l10n->t('No Talk rooms are available or you don\'t have permission to view them.'),
                 'bot_password' => $this->l10n->t('Bot App Password'),
-                'bot_password_desc' => $this->l10n->t('App password for the "talk-bot" user. Create one in Settings → talk-bot → Devices & sessions.'),
+                'bot_password_desc' => $this->l10n->t('App password for the "talk-bot" bot user account (not a regular user). Create one in Personal Settings → Security → Devices & sessions.'),
                 'sender_name' => $this->l10n->t('Default Sender Name'),
                 'sender_name_desc' => $this->l10n->t('Name used when posting messages as the bot.'),
                 'image_retention' => $this->l10n->t('Image Retention (days)'),