feat(project): optimize image imports and converter

- Optimize imported scene preview images (smart WebP/JPEG/PNG, preserve alpha, keep pixel size)

- Update converter to re-encode existing image assets with same algorithm

- Improve import/export progress overlay and reduce presentation slide stutter

Made-with: Cursor

app/renderer/editor/state/projectState.ts

@@ -10,6 +10,7 @@ type State = {
   projects: ProjectSummary[];
   project: Project | null;
   selectedSceneId: SceneId | null;
+  zipProgress: { kind: 'import' | 'export'; percent: number; stage: string; detail?: string } | null;
 };
 
 type Actions = {
@@ -27,6 +28,7 @@ type Actions = {
       title?: string;
       description?: string;
       previewAssetId?: AssetId | null;
+      previewThumbAssetId?: AssetId | null;
       previewAssetType?: 'image' | 'video' | null;
       previewVideoAutostart?: boolean;
       previewRotationDeg?: 0 | 90 | 180 | 270;
@@ -58,7 +60,12 @@ function randomId(prefix: string): string {
 
 export function useProjectState(licenseActive: boolean): readonly [State, Actions] {
   const api = getDndApi();
-  const [state, setState] = useState<State>({ projects: [], project: null, selectedSceneId: null });
+  const [state, setState] = useState<State>({
+    projects: [],
+    project: null,
+    selectedSceneId: null,
+    zipProgress: null,
+  });
   const projectRef = useRef<Project | null>(null);
   /** Bumps on mutations / refresh; initial license load only applies if still current (avoids racing late list/get over newer state). */
   const projectDataEpochRef = useRef(0);
@@ -66,6 +73,43 @@ export function useProjectState(licenseActive: boolean): readonly [State, Action
     projectRef.current = state.project;
   }, [state.project]);
 
+  useEffect(() => {
+    const offImport = api.on(ipcChannels.project.importZipProgress, (evt) => {
+      const e = evt as unknown as { percent: number; stage: string; detail?: string };
+      setState((s) => ({
+        ...s,
+        zipProgress: {
+          kind: 'import',
+          percent: e.percent,
+          stage: e.stage,
+          ...(e.detail ? { detail: e.detail } : null),
+        },
+      }));
+      if (e.stage === 'done' || e.percent >= 100) {
+        setTimeout(() => setState((s) => ({ ...s, zipProgress: null })), 450);
+      }
+    });
+    const offExport = api.on(ipcChannels.project.exportZipProgress, (evt) => {
+      const e = evt as unknown as { percent: number; stage: string; detail?: string };
+      setState((s) => ({
+        ...s,
+        zipProgress: {
+          kind: 'export',
+          percent: e.percent,
+          stage: e.stage,
+          ...(e.detail ? { detail: e.detail } : null),
+        },
+      }));
+      if (e.stage === 'done' || e.percent >= 100) {
+        setTimeout(() => setState((s) => ({ ...s, zipProgress: null })), 450);
+      }
+    });
+    return () => {
+      offImport();
+      offExport();
+    };
+  }, [api]);
+
   const actions = useMemo<Actions>(() => {
     const refreshProjects = async () => {
       projectDataEpochRef.current += 1;
@@ -99,6 +143,7 @@ export function useProjectState(licenseActive: boolean): readonly [State, Action
         title: `Новая сцена`,
         description: '',
         previewAssetId: null,
+        previewThumbAssetId: null,
         previewAssetType: null,
         previewVideoAutostart: false,
         previewRotationDeg: 0,
@@ -153,6 +198,7 @@ export function useProjectState(licenseActive: boolean): readonly [State, Action
         title?: string;
         description?: string;
         previewAssetId?: AssetId | null;
+        previewThumbAssetId?: AssetId | null;
         previewAssetType?: 'image' | 'video' | null;
         previewVideoAutostart?: boolean;
         previewRotationDeg?: 0 | 90 | 180 | 270;
@@ -171,6 +217,9 @@ export function useProjectState(licenseActive: boolean): readonly [State, Action
           ...(patch.title !== undefined ? { title: patch.title } : null),
           ...(patch.description !== undefined ? { description: patch.description } : null),
           ...(patch.previewAssetId !== undefined ? { previewAssetId: patch.previewAssetId } : null),
+          ...(patch.previewThumbAssetId !== undefined
+            ? { previewThumbAssetId: patch.previewThumbAssetId }
+            : null),
           ...(patch.previewAssetType !== undefined ? { previewAssetType: patch.previewAssetType } : null),
           ...(patch.previewVideoAutostart !== undefined
             ? { previewVideoAutostart: patch.previewVideoAutostart }
@@ -342,7 +391,7 @@ export function useProjectState(licenseActive: boolean): readonly [State, Action
     if (!licenseActive) {
       queueMicrotask(() => {
         projectDataEpochRef.current += 1;
-        setState({ projects: [], project: null, selectedSceneId: null });
+        setState({ projects: [], project: null, selectedSceneId: null, zipProgress: null });
       });
       return;
     }