refactor: standalone dashboard folders with index.html, zip-based import/export (.tsd/.tss/.tsp)

- Each dashboard is now a self-contained folder: manifest.json + index.html
- Auto-scan dashboards/ and data/dashboards/ on startup
- Export: .tsd (dashboards), .tss (scenes), .tsp (game plugins) - all zip format
- Dashboard index.html is complete standalone page (WS + data binding)
- Aspect ratio constraints handled in each dashboard's own JS
- Removed template-based dashboard rendering in favor of static serve
- Import via file upload endpoints, export via direct file download

models/scene.py

@@ -1,7 +1,10 @@
 from __future__ import annotations
 
+import io
 import json
+import shutil
 import uuid
+import zipfile
 from dataclasses import dataclass, field, asdict
 from datetime import datetime
 from pathlib import Path
@@ -124,24 +127,28 @@ class SceneManager:
             return True
         return False
 
-    def export_scene(self, scene_id: str) -> dict[str, Any] | None:
-        scene = self.get(scene_id)
-        if not scene:
+    def export_scene_zip(self, scene_id: str) -> bytes | None:
+        filepath = SCENES_DIR / f"{scene_id}.json"
+        if not filepath.exists():
             return None
-        return {
-            "type": "scene",
-            "version": "1.0",
-            "data": scene,
-        }
+        buf = io.BytesIO()
+        with zipfile.ZipFile(buf, 'w', zipfile.ZIP_DEFLATED) as zf:
+            zf.write(filepath, "scene.json")
+        logger.info("Scene exported as zip: %s", scene_id)
+        return buf.getvalue()
 
-    def import_scene(self, data: dict[str, Any]) -> bool:
-        if data.get("type") != "scene":
+    def import_scene_zip(self, zip_data: bytes) -> bool:
+        try:
+            with zipfile.ZipFile(io.BytesIO(zip_data), 'r') as zf:
+                if "scene.json" not in zf.namelist():
+                    logger.error("No scene.json found in zip")
+                    return False
+                data = json.loads(zf.read("scene.json").decode('utf-8'))
+                scene = Scene.from_dict(data)
+                return self.save(scene)
+        except Exception as e:
+            logger.error("Failed to import scene zip: %s", e)
             return False
-        scene_data = data.get("data", {})
-        if "id" not in scene_data:
-            scene_data["id"] = str(uuid.uuid4())
-        scene = Scene.from_dict(scene_data)
-        return self.save(scene)
 
 
 scene_manager = SceneManager()