fix(merge-split): fix premature 100% progress, add ffmpeg preflight, clean partial splits, use locale metaLabel

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/main.ts

@@ -3002,6 +3002,11 @@ async function processDownloadMergeGroup(
             return { success: false, error: 'Streamlink fehlt.' };
         }
 
+        const ffmpegReady = await ensureFfmpegInstalled();
+        if (!ffmpegReady) {
+            return { success: false, error: 'FFmpeg fehlt.' };
+        }
+
         const streamer = mg.items[0].streamer.replace(/[^a-zA-Z0-9_-]/g, '');
         const date = new Date(mg.items[0].date);
         const dateStr = `${date.getDate().toString().padStart(2, '0')}.${(date.getMonth() + 1).toString().padStart(2, '0')}.${date.getFullYear()}`;
@@ -3165,7 +3170,7 @@ async function processDownloadMergeGroup(
             });
         },
         (currentPart, totalParts) => {
-            const overallProgress = 90 + (currentPart / totalParts) * 10; // split = 90-100%
+            const overallProgress = 90 + ((currentPart - 1) / totalParts) * 10; // split = 90-100%
             onProgress({
                 id: item.id,
                 progress: overallProgress,
@@ -3179,6 +3184,10 @@ async function processDownloadMergeGroup(
     );
 
     if (!splitResult.success) {
+        // Clean up any partial split files
+        for (const partFile of splitResult.files) {
+            try { if (fs.existsSync(partFile)) fs.unlinkSync(partFile); } catch { }
+        }
         return { success: false, error: 'FFmpeg Split fehlgeschlagen.' };
     }
 

src/renderer-queue.ts

@@ -219,7 +219,7 @@ function renderQueue(): void {
             ? '<svg class="merge-group-icon" viewBox="0 0 24 24" fill="currentColor" width="14" height="14"><path d="M17 20.41L18.41 19 15 15.59 13.59 17 17 20.41zM7.5 8H11v5.59L5.59 19 7 20.41l6-6V8h3.5L12 3.5 7.5 8z"/></svg> '
             : '';
         const mergeMetaExtra = isMergeGroup
-            ? ` (${item.mergeGroup!.items.length} VODs)`
+            ? ` (${UI_TEXT.mergeGroup.metaLabel.replace('{count}', String(item.mergeGroup!.items.length))})`
             : '';
 
         return `