Move default templates to .jinja2 files + add live preview + update CLAUDE.md

Templates:
- Default EN/RU templates moved from inline Python strings to
  14 .jinja2 files in templates/{en,ru}/ directory
- Properly formatted with readable indentation and Jinja2
  whitespace control ({%- -%})
- load_default_templates(locale) loads from files on first access
- Seed function uses file loader instead of inline dicts

Preview:
- New POST /api/template-configs/preview-raw endpoint: renders
  arbitrary Jinja2 text with sample data (for live editing preview)
- Route ordering fixed: /variables before /{config_id}

CLAUDE.md:
- Added Frontend Architecture Notes (i18n, Svelte 5 runes, auth
  flow, Tailwind v4 quirks)
- Added Backend Architecture Notes (SQLAlchemy+aiohttp greenlet
  issue, SandboxedEnvironment import, system-owned entities,
  FastAPI route ordering, __pycache__)

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

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

@@ -141,20 +141,70 @@ class TemplateConfig(SQLModel, table=True):
     created_at: datetime = Field(default_factory=_utcnow)
 
 
-# --- Default template content (EN) ---
+# --- Default template loading from .jinja2 files ---
 
-DEFAULT_TEMPLATE_EN = {
-    "message_assets_added": """📷 {{ added_count }} new photo(s) added to album "{{ album_name }}".\
-{% if people %}
-👤 {{ people | join(", ") }}{% endif %}\
-{% if added_assets %}
-{% for asset in added_assets %}\
-  • {% if asset.type == "VIDEO" %}🎬{% else %}🖼️{% endif %} {{ asset.filename }}\
-{% if asset.city %} 📍 {{ asset.city }}{% if asset.country %}, {{ asset.country }}{% endif %}{% endif %}\
-{% if asset.is_favorite %} ❤️{% endif %}
-{% endfor %}\
-{% endif %}\
-{{ video_warning }}""",
+from pathlib import Path as _Path
+
+_TEMPLATES_DIR = _Path(__file__).parent.parent / "templates"
+
+_SLOT_TO_FILE = {
+    "message_assets_added": "assets_added.jinja2",
+    "message_assets_removed": "assets_removed.jinja2",
+    "message_album_renamed": "album_renamed.jinja2",
+    "message_album_deleted": "album_deleted.jinja2",
+    "periodic_summary_message": "periodic_summary.jinja2",
+    "scheduled_assets_message": "scheduled_assets.jinja2",
+    "memory_mode_message": "memory_mode.jinja2",
+}
+
+
+def load_default_templates(locale: str) -> dict[str, str]:
+    """Load default template files for a locale (en/ru)."""
+    result = {}
+    locale_dir = _TEMPLATES_DIR / locale
+    for slot, filename in _SLOT_TO_FILE.items():
+        path = locale_dir / filename
+        if path.exists():
+            result[slot] = path.read_text(encoding="utf-8").strip()
+        else:
+            result[slot] = ""
+    return result
+
+
+# Lazy-loaded defaults (loaded from files on first access)
+DEFAULT_TEMPLATE_EN: dict[str, str] = {}
+DEFAULT_TEMPLATE_RU: dict[str, str] = {}
+
+
+def get_default_templates(locale: str) -> dict[str, str]:
+    """Get default templates, loading from files on first call."""
+    global DEFAULT_TEMPLATE_EN, DEFAULT_TEMPLATE_RU
+    if locale == "ru":
+        if not DEFAULT_TEMPLATE_RU:
+            DEFAULT_TEMPLATE_RU = load_default_templates("ru")
+        return DEFAULT_TEMPLATE_RU
+    if not DEFAULT_TEMPLATE_EN:
+        DEFAULT_TEMPLATE_EN = load_default_templates("en")
+    return DEFAULT_TEMPLATE_EN
+
+
+_INLINE_TEMPLATES_REMOVED = {
+    "message_assets_added": (
+        '📷 {{ added_count }} new photo(s) added to album "{{ album_name }}".\n'
+        '{%- if people %}\n'
+        '👤 {{ people | join(", ") }}\n'
+        '{%- endif %}'
+        '{%- if added_assets %}\n'
+        '{%- for asset in added_assets %}\n'
+        '  • {%- if asset.type == "VIDEO" %} 🎬{% else %} 🖼️{% endif %} {{ asset.filename }}'
+        '{%- if asset.city %} 📍 {{ asset.city }}'
+        '{%- if asset.country %}, {{ asset.country }}{% endif %}'
+        '{%- endif %}'
+        '{%- if asset.is_favorite %} ❤️{% endif %}\n'
+        '{%- endfor %}'
+        '{%- endif %}'
+        '{{ video_warning }}'
+    ),
 
     "message_assets_removed": '🗑️ {{ removed_count }} photo(s) removed from album "{{ album_name }}".',
 
@@ -162,36 +212,49 @@ DEFAULT_TEMPLATE_EN = {
 
     "message_album_deleted": '🗑️ Album "{{ album_name }}" was deleted.',
 
-    "periodic_summary_message": """📋 Tracked Albums Summary ({{ albums | length }} albums):\
-{% for album in albums %}
-  • {{ album.name }}: {{ album.asset_count }} assets{% if album.url %} — {{ album.url }}{% endif %}\
-{% endfor %}""",
+    "periodic_summary_message": (
+        '📋 Tracked Albums Summary ({{ albums | length }} albums):\n'
+        '{%- for album in albums %}\n'
+        '  • {{ album.name }}: {{ album.asset_count }} assets'
+        '{%- if album.url %} — {{ album.url }}{% endif %}\n'
+        '{%- endfor %}'
+    ),
 
-    "scheduled_assets_message": """📸 Photos from "{{ album_name }}":\
-{% for asset in assets %}
-  • {% if asset.type == "VIDEO" %}🎬{% else %}🖼️{% endif %} {{ asset.filename }}\
-{% endfor %}""",
+    "scheduled_assets_message": (
+        '📸 Photos from "{{ album_name }}":\n'
+        '{%- for asset in assets %}\n'
+        '  • {%- if asset.type == "VIDEO" %} 🎬{% else %} 🖼️{% endif %} {{ asset.filename }}\n'
+        '{%- endfor %}'
+    ),
 
-    "memory_mode_message": """📅 On this day:\
-{% for asset in assets %}
-  • {% if asset.type == "VIDEO" %}🎬{% else %}🖼️{% endif %} {{ asset.filename }} ({{ asset.created_at[:4] }})\
-{% endfor %}""",
+    "memory_mode_message": (
+        '📅 On this day:\n'
+        '{%- for asset in assets %}\n'
+        '  • {%- if asset.type == "VIDEO" %} 🎬{% else %} 🖼️{% endif %} {{ asset.filename }}'
+        ' ({{ asset.created_at[:4] }})\n'
+        '{%- endfor %}'
+    ),
 }
 
 # --- Default template content (RU) ---
 
 DEFAULT_TEMPLATE_RU = {
-    "message_assets_added": """📷 {{ added_count }} новых фото добавлено в альбом "{{ album_name }}".\
-{% if people %}
-👤 {{ people | join(", ") }}{% endif %}\
-{% if added_assets %}
-{% for asset in added_assets %}\
-  • {% if asset.type == "VIDEO" %}🎬{% else %}🖼️{% endif %} {{ asset.filename }}\
-{% if asset.city %} 📍 {{ asset.city }}{% if asset.country %}, {{ asset.country }}{% endif %}{% endif %}\
-{% if asset.is_favorite %} ❤️{% endif %}
-{% endfor %}\
-{% endif %}\
-{{ video_warning }}""",
+    "message_assets_added": (
+        '📷 {{ added_count }} новых фото добавлено в альбом "{{ album_name }}".\n'
+        '{%- if people %}\n'
+        '👤 {{ people | join(", ") }}\n'
+        '{%- endif %}'
+        '{%- if added_assets %}\n'
+        '{%- for asset in added_assets %}\n'
+        '  • {%- if asset.type == "VIDEO" %} 🎬{% else %} 🖼️{% endif %} {{ asset.filename }}'
+        '{%- if asset.city %} 📍 {{ asset.city }}'
+        '{%- if asset.country %}, {{ asset.country }}{% endif %}'
+        '{%- endif %}'
+        '{%- if asset.is_favorite %} ❤️{% endif %}\n'
+        '{%- endfor %}'
+        '{%- endif %}'
+        '{{ video_warning }}'
+    ),
 
     "message_assets_removed": '🗑️ {{ removed_count }} фото удалено из альбома "{{ album_name }}".',
 
@@ -199,20 +262,28 @@ DEFAULT_TEMPLATE_RU = {
 
     "message_album_deleted": '🗑️ Альбом "{{ album_name }}" был удалён.',
 
-    "periodic_summary_message": """📋 Сводка альбомов ({{ albums | length }}):\
-{% for album in albums %}
-  • {{ album.name }}: {{ album.asset_count }} файлов{% if album.url %} — {{ album.url }}{% endif %}\
-{% endfor %}""",
+    "periodic_summary_message": (
+        '📋 Сводка альбомов ({{ albums | length }}):\n'
+        '{%- for album in albums %}\n'
+        '  • {{ album.name }}: {{ album.asset_count }} файлов'
+        '{%- if album.url %} — {{ album.url }}{% endif %}\n'
+        '{%- endfor %}'
+    ),
 
-    "scheduled_assets_message": """📸 Фото из "{{ album_name }}":\
-{% for asset in assets %}
-  • {% if asset.type == "VIDEO" %}🎬{% else %}🖼️{% endif %} {{ asset.filename }}\
-{% endfor %}""",
+    "scheduled_assets_message": (
+        '📸 Фото из "{{ album_name }}":\n'
+        '{%- for asset in assets %}\n'
+        '  • {%- if asset.type == "VIDEO" %} 🎬{% else %} 🖼️{% endif %} {{ asset.filename }}\n'
+        '{%- endfor %}'
+    ),
 
-    "memory_mode_message": """📅 В этот день:\
-{% for asset in assets %}
-  • {% if asset.type == "VIDEO" %}🎬{% else %}🖼️{% endif %} {{ asset.filename }} ({{ asset.created_at[:4] }})\
-{% endfor %}""",
+    "memory_mode_message": (
+        '📅 В этот день:\n'
+        '{%- for asset in assets %}\n'
+        '  • {%- if asset.type == "VIDEO" %} 🎬{% else %} 🖼️{% endif %} {{ asset.filename }}'
+        ' ({{ asset.created_at[:4] }})\n'
+        '{%- endfor %}'
+    ),
 }