fix(studio): polish media panel UX and preserve selection on undo

- Move Timing + Media sections above Layout in the Design panel
- Remove LayerTree from Design panel (redundant with Layers tab)
- Replace Rate and Media Start with sliders matching Volume's UX
- Replace Position DetailField with SelectField to match Fit height
- Remove Poster field (not useful for HyperFrames compositions)
- Show absolute filesystem path for Source (resolves symlinks)
- Add Copy button for source path with checkmark feedback
- Preserve element selection on undo/redo instead of clearing it

packages/studio/src/components/StudioRightPanel.tsx

@@ -12,8 +12,7 @@ import {
 
 /** Motion data without targeting metadata. */
 type StudioMotionData = Omit<StudioGsapMotion, "kind" | "target" | "updatedAt">;
-import { useCallback } from "react";
-import { resolveDomEditSelection, type DomEditLayerItem } from "./editor/domEditing";
+
 import { useStudioContext } from "../contexts/StudioContext";
 import { usePanelLayoutContext } from "../contexts/PanelLayoutContext";
 import { useFileManagerContext } from "../contexts/FileManagerContext";
@@ -67,23 +66,10 @@ export function StudioRightPanel({
     handleAskAgent,
     handleDomMotionCommit,
     handleDomMotionClear,
-    applyDomSelection,
   } = useDomEditContext();
 
-  const { assets, fontAssets, handleImportFiles, handleImportFonts } = useFileManagerContext();
-
-  const isMasterView = !activeCompPath || activeCompPath === "index.html";
-  const handleSelectLayer = useCallback(
-    (layer: DomEditLayerItem) => {
-      const selection = resolveDomEditSelection(layer.element, {
-        activeCompositionPath: activeCompPath,
-        isMasterView,
-        preferClipAncestor: false,
-      });
-      if (selection) applyDomSelection(selection);
-    },
-    [activeCompPath, isMasterView, applyDomSelection],
-  );
+  const { assets, fontAssets, projectDir, handleImportFiles, handleImportFonts } =
+    useFileManagerContext();
 
   const renderJobs = renderQueue.jobs as RenderJob[];
 
@@ -164,6 +150,7 @@ export function StudioRightPanel({
               ) : designPanelActive ? (
                 <PropertyPanel
                   projectId={projectId}
+                  projectDir={projectDir}
                   assets={assets}
                   element={domEditGroupSelections.length > 1 ? null : domEditSelection}
                   multiSelectCount={domEditGroupSelections.length}
@@ -183,8 +170,6 @@ export function StudioRightPanel({
                   onImportAssets={handleImportFiles}
                   fontAssets={fontAssets}
                   onImportFonts={handleImportFonts}
-                  activeCompositionPath={activeCompPath}
-                  onSelectLayer={handleSelectLayer}
                 />
               ) : motionPanelActive ? (
                 <MotionPanel