feat: 构建系统重构 + VCHSM 架构迁移 + 右键菜单修复 + 尺寸参数统一

## 构建、打包与分发系统重构 (build/)

- 构建系统收敛至 build/ 目录：build.mjs + electron-builder.js + 6 个脚本

- electron-builder 配置从 package.json 提取为 build/electron-builder.js

- 新增 --edition (personal/enterprise) 和 --channel (stable/beta/alpha) 参数

- OSS 路径按渠道隔离

- 新增 pre-build-check.mjs：Git/CHANGELOG/版本/环境变量校验

- 新增 bump-version.mjs：版本号管理 + CHANGELOG 自动生成

- updater.ts 发送 channel/edition/deviceFingerprint

- 新增 src/shared/utils/rollout.ts 灰度测试工具

- 新增 10 条 NPM 脚本

## VCHSM 五层架构迁移

- 7 个业务模块 + ~500 处导入路径同步

## 修复

- MediaCardContextMenu 改用共享 ContextMenu 组件

- ComboBox 尺寸参数显示统一 (size-format.ts)

## 文档

- UpdateA.md / build/README.md / README.md / .env.example 更新

Co-Authored-By: Claude <noreply@anthropic.com>

src/modules/canvas/hooks/useDirectoryScan.ts

@@ -0,0 +1,164 @@
+// ============================================================
+// useDirectoryScan — 目录扫描 Hook
+//
+// 根据 selectedProject / selectedEpisode / selectedShot / currentStage
+// 智能选择扫描策略：
+//   - Assets 阶段 → scanAssetFiles（深度递归扫描 assets/）
+//   - 非 Assets 阶段 → scanStageFiles（扫描 shots/{ep}/{shot}/{stage}/）
+//
+// 防抖 300ms，窗口聚焦时自动重扫。
+// ============================================================
+
+import { useEffect, useRef, useCallback } from 'react';
+import { logger } from '@/shared/utils/bus';
+import { useCanvasStore } from '../stores/useCanvasStore';
+
+export function useDirectoryScan() {
+    // 选择性订阅
+    const workspaceRoot = useCanvasStore((s) => s.workspaceRoot);
+    const selectedProject = useCanvasStore((s) => s.selectedProject);
+    const selectedEpisode = useCanvasStore((s) => s.selectedEpisode);
+    const selectedShot = useCanvasStore((s) => s.selectedShot);
+    const currentStage = useCanvasStore((s) => s.currentStage);
+    const assetTypeFilter = useCanvasStore((s) => s.assetTypeFilter);
+    const keywordQuery = useCanvasStore((s) => s.keywordQuery);
+    const tagQuery = useCanvasStore((s) => s.tagQuery);
+
+    const clearItems = useCanvasStore((s) => s.clearItems);
+    const appendItems = useCanvasStore((s) => s.appendItems);
+    const setIsScanning = useCanvasStore((s) => s.setIsScanning);
+    const setScanProgress = useCanvasStore((s) => s.setScanProgress);
+    const getDataSource = useCanvasStore((s) => s.getDataSource);
+    const getProjectPath = useCanvasStore((s) => s.getProjectPath);
+
+    // 扫描 abort 控制器 ref
+    const abortRef = useRef<AbortController | null>(null);
+    // 防抖 timer
+    const debounceRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+    // 当前 epoch
+    const epochRef = useRef(0);
+
+    const doScan = useCallback(async () => {
+        const projectPath = getProjectPath();
+        if (!projectPath) {
+            console.log('[useDirectoryScan] ⏸️ 跳过扫描：projectPath 为空（未选择项目）');
+            clearItems();
+            return;
+        }
+
+        // 取消之前的扫描
+        abortRef.current?.abort();
+        const controller = new AbortController();
+        abortRef.current = controller;
+
+        const epoch = ++epochRef.current;
+
+        const isAssets = currentStage === 'Assets';
+
+        console.log(`[useDirectoryScan] 🔍 开始扫描 (epoch=${epoch})`, {
+            projectPath,
+            stage: currentStage,
+            isAssets,
+            selectedEpisode: selectedEpisode || '(未选)',
+            selectedShot: selectedShot || '(未选)',
+        });
+
+        if (!isAssets && (!selectedEpisode || !selectedShot)) {
+            console.log('[useDirectoryScan] ⏸️ 跳过扫描：非 Assets 阶段需先选择集数和镜头');
+            clearItems();
+            return;
+        }
+
+        const t0 = performance.now();
+        setIsScanning(true);
+        setScanProgress({ found: 0, currentPath: '' });
+
+        try {
+            const dataSource = getDataSource();
+            let entries: Array<{ path: string; fileName: string; ext: string; fileSize: number; modifiedAt: string }>;
+
+            if (isAssets) {
+                // Assets 阶段：深度递归扫描
+                entries = await dataSource.scanAssetFiles({
+                    projectPath,
+                    assetTypeFilter,
+                });
+            } else {
+                // 非 Assets 阶段：扫描指定镜头的阶段目录
+                entries = await dataSource.scanStageFiles({
+                    projectPath,
+                    episode: selectedEpisode!,
+                    shot: selectedShot!,
+                    stage: currentStage,
+                });
+            }
+
+            // Epoch 检查
+            if (epoch !== epochRef.current) {
+                console.log(`[useDirectoryScan] ⚠️ epoch 过期 (${epoch} → ${epochRef.current})，丢弃结果`);
+                return;
+            }
+            if (controller.signal.aborted) {
+                console.log('[useDirectoryScan] ⚠️ 扫描已被 abort，丢弃结果');
+                return;
+            }
+
+            const elapsed = (performance.now() - t0).toFixed(0);
+            console.log(`[useDirectoryScan] ✅ 扫描完成 (epoch=${epoch}, 耗时=${elapsed}ms)`, {
+                totalEntries: entries.length,
+            });
+
+            clearItems();
+            appendItems(entries);
+            setScanProgress(null);
+        } catch (err) {
+            if (controller.signal.aborted || epoch !== epochRef.current) return;
+            logger.warn('canvas', '目录扫描失败', err instanceof Error ? err : new Error(String(err)));
+        } finally {
+            if (epoch === epochRef.current) {
+                setIsScanning(false);
+            }
+        }
+    }, [
+        selectedProject,
+        selectedEpisode,
+        selectedShot,
+        currentStage,
+        assetTypeFilter,
+        clearItems,
+        appendItems,
+        setIsScanning,
+        setScanProgress,
+        getDataSource,
+        getProjectPath,
+    ]);
+
+    // 防抖触发扫描
+    useEffect(() => {
+        if (debounceRef.current) {
+            clearTimeout(debounceRef.current);
+        }
+        debounceRef.current = setTimeout(() => {
+            void doScan();
+        }, 100);
+
+        return () => {
+            if (debounceRef.current) {
+                clearTimeout(debounceRef.current);
+            }
+        };
+    }, [doScan, workspaceRoot, keywordQuery, tagQuery]);
+
+    // 窗口聚焦时重新扫描
+    useEffect(() => {
+        const handleFocus = () => {
+            setTimeout(() => {
+                void doScan();
+            }, 500);
+        };
+        window.addEventListener('focus', handleFocus);
+        return () => window.removeEventListener('focus', handleFocus);
+    }, [doScan]);
+
+    return { rescan: doScan };
+}