feat: smart video size warnings + Jinja2 template autocomplete

Video size warnings:
- Add file_size field to ImmichAssetInfo from exifInfo.fileSizeInByte
- Expose per-target max_video_size (50 MB for Telegram, none for others)
- Compute has_oversized_videos and per-asset oversized flag in template context
- Default templates show warning only when videos actually exceed the limit
- Templates no longer hardcode Telegram-specific logic

Template autocomplete:
- New jinja-autocomplete.ts engine with contextual completions
- Top-level variables ({{ }}), asset/album fields (dot access in loops),
  Jinja2 filters (|), block tags ({% %}), and loop.* special vars
- JinjaEditor accepts optional variables prop via CodeMirror Compartment
- Wired into template-configs and command-template-configs pages

Also: fix template emoji (📷 → 📎) and sync sample_context with new vars.

packages/server/src/notify_bridge_server/api/template_configs.py

@@ -150,6 +150,9 @@ async def get_template_variables():
         "target_type": "Target type: 'telegram' or 'webhook'",
         "has_videos": "Whether added assets contain videos (boolean)",
         "has_photos": "Whether added assets contain photos (boolean)",
+        "has_oversized_videos": "Whether any video exceeds the target's size limit (boolean)",
+        "max_video_size": "Target video size limit in bytes (null if no limit)",
+        "max_video_size_mb": "Target video size limit in MB (null if no limit)",
         # Immich aliases
         "album_name": "Alias for collection_name",
         "album_id": "Alias for collection_id",
@@ -178,6 +181,8 @@ async def get_template_variables():
         "city": "City name",
         "state": "State/region name",
         "country": "Country name",
+        "file_size": "File size in bytes (null if unknown)",
+        "oversized": "Whether video exceeds the target's size limit (boolean, videos only)",
         "public_url": "Per-asset public share URL (empty if no album link)",
         "url": "Public viewer URL (if shared)",
         "download_url": "Direct download URL (if shared)",