Move preview button to per-slot in edit form, remove card dropdown

- Preview button always visible next to Variables for each template slot
- Remove \n\n prefix from video_warning default value
- Use conditional {% if video_warning %} with blank line in templates
- Fix all .jinja2 files and inline defaults to match
- Add SVG favicon (camera + notification dot)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/server/src/immich_watcher_server/database/models.py

@@ -136,7 +136,7 @@ class TemplateConfig(SQLModel, table=True):
     # Settings
     date_format: str = Field(default="%d.%m.%Y, %H:%M UTC")
     video_warning: str = Field(
-        default="\n\n⚠️ Note: Videos may not be sent due to Telegram's 50 MB file size limit."
+        default="⚠️ Note: Videos may not be sent due to Telegram's 50 MB file size limit."
     )
 
     created_at: datetime = Field(default_factory=_utcnow)
@@ -204,7 +204,7 @@ _INLINE_TEMPLATES_REMOVED = {
         '{%- if asset.is_favorite %} ❤️{% endif %}\n'
         '{%- endfor %}'
         '{%- endif %}'
-        '{{ video_warning }}'
+        '{%- if video_warning %}\n\n{{ video_warning }}{%- endif %}'
     ),
 
     "message_assets_removed": '🗑️ {{ removed_count }} photo(s) removed from album "{{ album_name }}".',
@@ -254,7 +254,7 @@ DEFAULT_TEMPLATE_RU = {
         '{%- if asset.is_favorite %} ❤️{% endif %}\n'
         '{%- endfor %}'
         '{%- endif %}'
-        '{{ video_warning }}'
+        '{%- if video_warning %}\n\n{{ video_warning }}{%- endif %}'
     ),
 
     "message_assets_removed": '🗑️ {{ removed_count }} фото удалено из альбома "{{ album_name }}".',