feat: auto-detect preview image format (jpg/png/webp/gif)

models/dashboard.py

@@ -35,6 +35,7 @@ class DashboardTheme:
     updated_at: str = ""
     is_builtin: bool = False
     dir_path: str = ""
+    preview_ext: str = ""
 
     def to_dict(self) -> dict[str, Any]:
         return {
@@ -51,6 +52,7 @@ class DashboardTheme:
             "created_at": self.created_at,
             "updated_at": self.updated_at,
             "is_builtin": self.is_builtin,
+            "preview_ext": self.preview_ext,
         }
 
     @classmethod
@@ -59,6 +61,12 @@ class DashboardTheme:
             with open(manifest_path, "r", encoding="utf-8") as f:
                 data = json.load(f)
             config = data.get("config", {})
+            dir_path = manifest_path.parent
+            preview_ext = ""
+            for ext in ["jpg", "jpeg", "png", "webp", "gif"]:
+                if (dir_path / f"preview.{ext}").exists():
+                    preview_ext = ext
+                    break
             return cls(
                 id=data.get("id", manifest_path.parent.name),
                 name=data.get("name", manifest_path.parent.name),
@@ -74,6 +82,7 @@ class DashboardTheme:
                 updated_at=data.get("updated_at", ""),
                 is_builtin=is_builtin,
                 dir_path=str(manifest_path.parent),
+                preview_ext=preview_ext,
             )
         except Exception as e:
             logger.error("Failed to load dashboard manifest %s: %s", manifest_path, e)