feat(merge-split): numbered selection instead of checkboxes, user-defined merge order

Replace checkboxes with numbered selectors (1, 2, 3...) that show the
merge order. Click order determines VOD sequence in the merged result.
Chronological auto-sort removed — user controls the order.

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

src/main.ts

@@ -3870,8 +3870,10 @@ ipcMain.handle('create-merge-group', (_, itemIds: string[]) => {
         return downloadQueue;
     }
 
-    // Sort chronologically by ISO timestamp (handles same-day different times)
-    const sorted = [...selectedItems].sort((a, b) => new Date(a.date).getTime() - new Date(b.date).getTime());
+    // Preserve user-defined order from renderer (itemIds array order)
+    const sorted = itemIds
+        .map(id => selectedItems.find(item => item.id === id))
+        .filter((item): item is QueueItem => item !== undefined);
 
     // Calculate total duration
     const totalDurationSec = sorted.reduce((sum, item) => sum + parseDuration(item.duration_str), 0);

src/renderer-queue.ts

@@ -140,10 +140,11 @@ function getQueueMetaText(item: QueueItem): string {
 }
 
 function toggleQueueSelection(id: string): void {
-    if (selectedQueueIds.has(id)) {
-        selectedQueueIds.delete(id);
+    const index = selectedQueueIds.indexOf(id);
+    if (index >= 0) {
+        selectedQueueIds.splice(index, 1);
     } else {
-        selectedQueueIds.add(id);
+        selectedQueueIds.push(id);
     }
     renderQueue();
     updateMergeGroupButton();
@@ -157,11 +158,11 @@ function updateMergeGroupButton(): void {
     const validIds = new Set(
         queue.filter(item => item.status === 'pending' && !item.mergeGroup).map(item => item.id)
     );
-    selectedQueueIds = new Set([...selectedQueueIds].filter(id => validIds.has(id)));
+    selectedQueueIds = selectedQueueIds.filter(id => validIds.has(id));
 
-    if (selectedQueueIds.size >= 2) {
+    if (selectedQueueIds.length >= 2) {
         btn.style.display = '';
-        btn.textContent = `${UI_TEXT.mergeGroup.btn} (${selectedQueueIds.size})`;
+        btn.textContent = `${UI_TEXT.mergeGroup.btn} (${selectedQueueIds.length})`;
         btn.disabled = false;
     } else {
         btn.style.display = 'none';
@@ -169,10 +170,10 @@ function updateMergeGroupButton(): void {
 }
 
 async function createMergeGroupFromSelection(): Promise<void> {
-    if (selectedQueueIds.size < 2) return;
+    if (selectedQueueIds.length < 2) return;
 
     const ids = [...selectedQueueIds];
-    selectedQueueIds.clear();
+    selectedQueueIds = [];
     queue = await window.api.createMergeGroup(ids);
     renderQueue();
     updateMergeGroupButton();
@@ -213,8 +214,9 @@ function renderQueue(): void {
         const progressClass = item.status === 'downloading' && !hasDeterminateProgress ? ' indeterminate' : '';
 
         const isMergeGroup = !!item.mergeGroup;
-        const showCheckbox = item.status === 'pending' && !isMergeGroup;
-        const isChecked = selectedQueueIds.has(item.id);
+        const showSelector = item.status === 'pending' && !isMergeGroup;
+        const selectionIndex = selectedQueueIds.indexOf(item.id);
+        const isSelected = selectionIndex >= 0;
         const mergeIcon = isMergeGroup
             ? '<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> '
             : '';
@@ -224,8 +226,8 @@ function renderQueue(): void {
 
         return `
             <div class="queue-item${isMergeGroup ? ' merge-group' : ''}">
-                ${showCheckbox
-                    ? `<input type="checkbox" class="queue-checkbox" ${isChecked ? 'checked' : ''} onchange="toggleQueueSelection('${item.id}')" />`
+                ${showSelector
+                    ? `<div class="queue-selector${isSelected ? ' selected' : ''}" onclick="toggleQueueSelection('${item.id}')">${isSelected ? selectionIndex + 1 : ''}</div>`
                     : ''
                 }
                 <div class="status ${item.status}"></div>

src/renderer-shared.ts

@@ -24,7 +24,7 @@ let currentStreamer: string | null = null;
 let isConnected = false;
 let downloading = false;
 let queue: QueueItem[] = [];
-let selectedQueueIds: Set<string> = new Set();
+let selectedQueueIds: string[] = [];
 
 let cutterFile: string | null = null;
 let cutterVideoInfo: VideoInfo | null = null;

src/styles.css

@@ -329,13 +329,30 @@ body {
     opacity: 1;
 }
 
-.queue-checkbox {
-    width: 14px;
-    height: 14px;
-    margin-top: 2px;
+.queue-selector {
+    width: 22px;
+    height: 22px;
+    border: 2px solid var(--text-secondary);
+    border-radius: 4px;
     cursor: pointer;
-    accent-color: var(--accent);
     flex-shrink: 0;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 12px;
+    font-weight: 700;
+    color: var(--bg-primary);
+    user-select: none;
+    transition: all 0.15s;
+}
+
+.queue-selector.selected {
+    background: var(--accent);
+    border-color: var(--accent);
+}
+
+.queue-selector:hover {
+    border-color: var(--accent);
 }
 
 .queue-item.merge-group {