fix: address CodeRabbit review feedback

- Fix telemetry drift reset: use nextExpectedMs - now for delay instead
  of stale drift value after baseline reset (avoids 1ms rapid sample)
- Use RECORDER_TIMESLICE_MS for mic fallback recorder (was hardcoded 1000)
- Return requested timeMs in extensionHost getCursorAt boundary clamps
- Remove premature null of webcam URL to prevent flicker on path change
- Use fs.realpath in IPC get-local-media-url to match media server check

electron/ipc/cursor/telemetry.ts

@@ -177,7 +177,7 @@ export function startCursorSampling() {
 			nextExpectedMs = now + CURSOR_SAMPLE_INTERVAL_MS;
 		}
 
-		const delay = Math.max(1, CURSOR_SAMPLE_INTERVAL_MS - drift);
+		const delay = Math.max(1, nextExpectedMs - now);
 		setCursorCaptureInterval(setTimeout(tick, delay));
 	};
 

electron/ipc/register/project.ts

@@ -379,12 +379,17 @@ export function registerProjectHandlers() {
     }
   });
 
-  ipcMain.handle('get-local-media-url', (_, filePath: string) => {
+  ipcMain.handle('get-local-media-url', async (_, filePath: string) => {
     const baseUrl = getMediaServerBaseUrl();
     if (!baseUrl || !filePath) {
       return { success: false as const };
     }
-    const resolved = path.resolve(filePath);
+    let resolved: string;
+    try {
+      resolved = await fs.realpath(path.resolve(filePath));
+    } catch {
+      return { success: false as const };
+    }
     if (!approvedLocalReadPaths.has(resolved)) {
       console.warn(`[get-local-media-url] Blocked unapproved path: ${resolved}`);
       return { success: false as const };

src/components/video-editor/VideoEditor.tsx

@@ -1807,7 +1807,6 @@ export default function VideoEditor() {
 			setResolvedWebcamVideoUrl(null);
 			return;
 		}
-		setResolvedWebcamVideoUrl(null);
 		void resolveVideoUrl(webcam.sourcePath).then((url) => {
 			if (!cancelled) setResolvedWebcamVideoUrl(url);
 		});

src/hooks/useScreenRecorder.ts

@@ -968,7 +968,7 @@ export function useScreenRecorder(): UseScreenRecorderReturn {
 									micFallbackChunks.current.push(event.data);
 								}
 							};
-							recorder.start(1000);
+							recorder.start(RECORDER_TIMESLICE_MS);
 							micFallbackRecorder.current = recorder;
 						} catch (micError) {
 							console.warn("Browser microphone fallback failed:", micError);

src/lib/extensions/extensionHost.ts

@@ -854,8 +854,8 @@ export class ExtensionHost {
 				const t = host._cursorTelemetry;
 				if (!t || t.length === 0) return null;
 
-				if (timeMs <= t[0].timeMs) return { ...t[0] };
-				if (timeMs >= t[t.length - 1].timeMs) return { ...t[t.length - 1] };
+				if (timeMs <= t[0].timeMs) return { ...t[0], timeMs };
+				if (timeMs >= t[t.length - 1].timeMs) return { ...t[t.length - 1], timeMs };
 
 				let lo = 0;
 				let hi = t.length - 1;