fix: address CodeRabbit review — fallback, i18n, return type cleanup

- Change ?? 99 fallback to ?? 100 in finalizing progress label
- Add editor.export.processingAudioEdits i18n key to all 5 locales
- Tighten sourceTimeToOutputTime return type to number (was number|null)
- Remove now-unused totalOutputDurationMs param from scheduleRegionForChunk
- Remove ?? fallbacks at call sites (function always returns a number)

src/components/video-editor/VideoEditor.tsx

@@ -4234,7 +4234,7 @@ export default function VideoEditor() {
 					})
 				: isExportFinalizing
 					? t("editor.exportStatus.finalizingPercent", "Finalizing {{percent}}%", {
-							percent: Math.round(exportFinalizingProgress ?? 99),
+							percent: Math.round(exportFinalizingProgress ?? 100),
 						})
 					: t("editor.exportStatus.completePercent", "{{percent}}% complete", {
 							percent: Math.round(exportProgress.percentage),

src/i18n/locales/en/editor.json

@@ -122,6 +122,9 @@
 		"complete": "Export complete",
 		"savedSuccessfully": "Your file was saved successfully."
 	},
+	"export": {
+		"processingAudioEdits": "Processing audio with speed/overlay edits"
+	},
 	"toolbar": {
 		"addLayer": "Add Layer",
 		"splitClip": "Split Clip (C)"

src/i18n/locales/es/editor.json

@@ -122,6 +122,9 @@
 		"complete": "Exportación completada",
 		"savedSuccessfully": "Tu archivo se guardó correctamente."
 	},
+	"export": {
+		"processingAudioEdits": "Procesando audio con ediciones de velocidad/superposición"
+	},
 	"toolbar": {
 		"addLayer": "Agregar capa",
 		"splitClip": "Dividir clip (C)"

src/i18n/locales/ko/editor.json

@@ -123,6 +123,9 @@
 		"complete": "내보내기 완료",
 		"savedSuccessfully": "파일이 성공적으로 저장되었습니다."
 	},
+	"export": {
+		"processingAudioEdits": "속도/오버레이 편집으로 오디오 처리 중"
+	},
 	"toolbar": {
 		"addLayer": "레이어 추가",
 		"splitClip": "클립 분할 (C)"

src/i18n/locales/nl/editor.json

@@ -123,6 +123,9 @@
 		"complete": "Export voltooid",
 		"savedSuccessfully": "Je bestand is succesvol opgeslagen."
 	},
+	"export": {
+		"processingAudioEdits": "Audio verwerken met snelheids-/overlay-bewerkingen"
+	},
 	"toolbar": {
 		"addLayer": "Laag toevoegen",
 		"splitClip": "Clip splitsen (C)"

src/i18n/locales/zh-CN/editor.json

@@ -122,6 +122,9 @@
 		"complete": "导出完成",
 		"savedSuccessfully": "文件已成功保存。"
 	},
+	"export": {
+		"processingAudioEdits": "正在处理带有速度/叠加编辑的音频"
+	},
 	"toolbar": {
 		"addLayer": "添加图层",
 		"splitClip": "拆分片段 (C)"

src/lib/exporter/audioEncoder.ts

@@ -611,9 +611,7 @@ export class AudioProcessor {
 		// Extend for audio regions that might exceed the video timeline
 		for (const { region } of regionEntries) {
 			const regionEndOutput = this.sourceTimeToOutputTime(region.endMs, slices);
-			if (regionEndOutput !== null) {
-				outputDurationMs = Math.max(outputDurationMs, regionEndOutput);
-			}
+			outputDurationMs = Math.max(outputDurationMs, regionEndOutput);
 		}
 
 		const numChannels = Math.min(primaryBuffer?.numberOfChannels ?? 2, 2);
@@ -744,7 +742,7 @@ export class AudioProcessor {
 			chunkIndex: number,
 		) => Promise<void>,
 	): Promise<void> {
-		const { slices, outputDurationMs, numChannels } = prepared;
+		const { slices, numChannels } = prepared;
 		let outputOffsetSec = 0;
 		const chunkCount = Math.ceil(totalOutputSec / OFFLINE_CHUNK_DURATION_SEC);
 
@@ -792,7 +790,6 @@ export class AudioProcessor {
 					buffer,
 					region,
 					slices,
-					outputDurationMs,
 					outputOffsetSec,
 					chunkSec,
 				);
@@ -814,13 +811,11 @@ export class AudioProcessor {
 		buffer: AudioBuffer,
 		region: AudioRegion,
 		slices: TimelineSlice[],
-		totalOutputDurationMs: number,
 		chunkOutputStartSec: number,
 		chunkDurationSec: number,
 	): void {
-		const outputStartMs = this.sourceTimeToOutputTime(region.startMs, slices) ?? 0;
-		const outputEndMs =
-			this.sourceTimeToOutputTime(region.endMs, slices) ?? totalOutputDurationMs;
+		const outputStartMs = this.sourceTimeToOutputTime(region.startMs, slices);
+		const outputEndMs = this.sourceTimeToOutputTime(region.endMs, slices);
 
 		let localStartSec = outputStartMs / 1000 - chunkOutputStartSec;
 		let localEndSec = outputEndMs / 1000 - chunkOutputStartSec;
@@ -1240,7 +1235,7 @@ export class AudioProcessor {
 	private sourceTimeToOutputTime(
 		sourceMs: number,
 		slices: TimelineSlice[],
-	): number | null {
+	): number {
 		let outputMs = 0;
 
 		for (const slice of slices) {