feat: 三栏比例缩放 + SeedanceContent视频上传 + 本地存储基建 (0.0.22)

三栏布局
- ResizeObserver 等比例分配替代固定默认值恢复
- 修复拖拽+窗口调整竞态卡死（needsRecalcRef 延迟补算）
- containerRef.current 动态读取 DOM 替代闭包 el

Seedance2Content
- 从占位文本重构为内容编排控件（文本+图片/视频/音频上传）
- 根据 spec.image_files/video_files/audio_files 动态渲染上传区域
- 值 JSON 序列化 → 提交时转 ContentItem[]（text/image_url/video_url/audio_url）

图片上传兼容视频文件
- buildAccept 根据 file_filter 区分 image/video 前缀
- createMediaBeforeUpload 动态放行 video/* MIME
- 公共模块 media-upload-utils.ts

本地存储基建
- sql.js (WASM SQLite) + safeStorage 加密持久化
- 8个IPC文件操作通道 + resolveSafe 路径穿越防护
- <userData>/heixiu-data/ 沙箱 + JWT用户隔离
- 7表DDL + 游标分页 + LRU媒体淘汰

其他
- 修复 errorMessageRef 渲染期写入警告
- 媒体预览回退直接URL（<img>无CORS限制）+ output_type类型补充
- CSP wasm-unsafe-eval + https: CDN媒体源

src/components/providers/SettingsProvider.tsx

@@ -8,6 +8,7 @@
 // ============================================================
 
 import { createContext, useContext, useState, useCallback, type ReactNode } from 'react';
+import { setOutputPath as saveOutputPath, setTeamRepoPath as saveTeamRepoPath } from '@/infrastructure/storage';
 
 // ---------- localStorage 键 ----------
 
@@ -108,6 +109,7 @@ export function SettingsProvider({ children }: SettingsProviderProps) {
    const setOutputPath = useCallback((path: string) => {
       setOutputPathState(path);
       writeStoredOutputPath(path);
+      try { saveOutputPath(path); } catch { /* db 未初始化则跳过 */ }
    }, []);
 
    const clearOutputPath = useCallback(() => {
@@ -120,6 +122,7 @@ export function SettingsProvider({ children }: SettingsProviderProps) {
    const setTeamRepoPath = useCallback((path: string) => {
       setTeamRepoPathState(path);
       writeStoredTeamRepoPath(path);
+      try { saveTeamRepoPath(path); } catch { /* db 未初始化则跳过 */ }
    }, []);
 
    const clearTeamRepoPath = useCallback(() => {