Add document type and content_type support for send_telegram_notification

- Add type: document as default media type (instead of photo)
- Add optional content_type field for explicit MIME type specification
- Documents are sent separately (Telegram API limitation for media groups)
- Default content types: image/jpeg (photo), video/mp4 (video), auto-detect (document)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

README.md

@@ -37,7 +37,7 @@ A Home Assistant custom integration that monitors [Immich](https://immich.app/)
 - **Services** - Custom service calls:
   - `immich_album_watcher.refresh` - Force immediate data refresh
   - `immich_album_watcher.get_assets` - Get assets from an album with filtering and ordering
-  - `immich_album_watcher.send_telegram_notification` - Send text, photo, video, or media group to Telegram
+  - `immich_album_watcher.send_telegram_notification` - Send text, photo, video, document, or media group to Telegram
 - **Share Link Management** - Button entities to create and delete share links:
   - Create/delete public (unprotected) share links
   - Create/delete password-protected share links
@@ -335,11 +335,12 @@ data:
 Send notifications to Telegram. Supports multiple formats:
 
 - **Text message** - When `urls` is empty or not provided
-- **Single photo** - When `urls` contains one photo
-- **Single video** - When `urls` contains one video
-- **Media group** - When `urls` contains multiple items
+- **Single document** - When `urls` contains one document (default type)
+- **Single photo** - When `urls` contains one photo (`type: photo`)
+- **Single video** - When `urls` contains one video (`type: video`)
+- **Media group** - When `urls` contains multiple photos/videos (documents are sent separately)
 
-The service downloads media from Immich and uploads it to Telegram, bypassing any CORS restrictions. Large lists of media are automatically split into multiple media groups based on the `max_group_size` parameter (default: 10 items per group).
+The service downloads media from Immich and uploads it to Telegram, bypassing any CORS restrictions. Large lists of photos and videos are automatically split into multiple media groups based on the `max_group_size` parameter (default: 10 items per group). Documents cannot be grouped and are sent individually.
 
 **File ID Caching:** When media is uploaded to Telegram, the service caches the returned `file_id`. Subsequent sends of the same media will use the cached `file_id` instead of re-uploading, significantly improving performance. The cache TTL is configurable in hub options (default: 48 hours, range: 1-168 hours). The cache is persistent across Home Assistant restarts and is stored per album.
 
@@ -357,6 +358,20 @@ data:
   disable_web_page_preview: true
 ```
 
+Single document (default):
+
+```yaml
+service: immich_album_watcher.send_telegram_notification
+target:
+  entity_id: sensor.album_name_asset_limit
+data:
+  chat_id: "-1001234567890"
+  urls:
+    - url: "https://immich.example.com/api/assets/xxx/original?key=yyy"
+      content_type: "image/heic"  # Optional: explicit MIME type
+  caption: "Original file"
+```
+
 Single photo:
 
 ```yaml
@@ -421,7 +436,7 @@ data:
 | Field | Description | Required |
 |-------|-------------|----------|
 | `chat_id` | Telegram chat ID to send to | Yes |
-| `urls` | List of media items with `url` and `type` (photo/video). Empty for text message. | No |
+| `urls` | List of media items with `url`, optional `type` (document/photo/video, default: document), and optional `content_type` (MIME type, e.g., `image/jpeg`). Empty for text message. Photos and videos can be grouped; documents are sent separately. | No |
 | `bot_token` | Telegram bot token (uses configured token if not provided) | No |
 | `caption` | For media: caption applied to first item. For text: the message text. Supports HTML formatting by default. | No |
 | `reply_to_message_id` | Message ID to reply to | No |