refactor(assets): vendor 资产迁入标准目录并全仓去除 zibll 标识

- assets/vendor 全量迁移: fontawesome5→assets/fontawesome5, css→assets/css,
  js→assets/js/runtime(避开 14 个同名自有文件), img 合并去重→assets/img,
  fonts→assets/fonts; 删除 assets/vendor
- libs 五个与 widgets/third-party 字节相同的库不重复入库, loader paths 改指向
- 运行时切换: _win.uri=assets 根, loader baseUrl=/js/runtime, enlighter 注入
  路径同步; PHP 7 个引用文件切换并改名 $zibll_*→$runtime_*
- 去品牌: Qinver 头注释/品牌 console.log/演示链接清除, 默认文案中性化
- 功能标识符改名: zib__→aksrt__, zib_ajax→aksrt_ajax, window.zib→
  window.aksrtLegacy, zibllblock/*→aksrtblock/*, .zib-widget→.aksrt-panel,
  .zib-slider→.aksrt-slider, zib_menu_options meta 键等
- 自有 CSS 改名: legacy-utilities/compat-vars/footer shell
- admin SPA 重建; 契约测试同步(路径/断言/文件更名)
- 例外保留: tests/visual 对照环境与 fixtures 前缀(外部 Zibll 产品引用)

验证: php -l 133 个改动文件通过; runtime 86 个 JS node --check 通过;
契约测试 68/70(2 个失败经 stash 对照确认为存量问题)

tests/widget-system/lazyload-contract.test.cjs

@@ -68,7 +68,7 @@ ${body}
 function sourceFiles(directory) {
   const output = [];
   for (const entry of fs.readdirSync(directory, { withFileTypes: true })) {
-    if (entry.name === '.git' || entry.name === '.claude' || entry.name === 'build' || entry.name === 'vendor' || entry.name === 'node_modules' || entry.name === 'third-party') continue;
+    if (entry.name === '.git' || entry.name === '.claude' || entry.name === 'build' || entry.name === 'vendor' || entry.name === 'runtime' || entry.name === 'node_modules' || entry.name === 'third-party') continue;
     if (/\.min\.(?:js|css)$/.test(entry.name)) continue;
     const full = path.join(directory, entry.name);
     if (entry.isDirectory()) output.push(...sourceFiles(full));
@@ -77,7 +77,7 @@ function sourceFiles(directory) {
   return output;
 }
 
-test('admin schemas expose the ten Zibll lazy fields and defaults', () => {
+test('admin schemas expose the ten legacy lazy fields and defaults', () => {
   const php = read('src/Admin/Schema/GlobalSchema.php');
   const vue = read('assets/admin/src/schema/sections/global/common.js');
   for (const [key, value] of Object.entries(lazyDefaults)) {
@@ -122,8 +122,8 @@ echo aksrt_lazy_content_images($html);
   assert.doesNotMatch(avatar, /loading=/);
 });
 
-test('Zibll owns lazySizes while AKSRT consumers share one image-attribute bridge', () => {
-  const runtime = read('assets/vendor/zibll/js/main.js');
+test('the legacy runtime owns lazySizes while AKSRT consumers share one image-attribute bridge', () => {
+  const runtime = read('assets/js/runtime/main.js');
   const bridge = read('assets/js/lazy-image-attr.js');
   const scripts = read('src/Core/ScriptsPart1c.php');
   const routeScripts = read('src/Core/ScriptsPart1b.php');
@@ -150,7 +150,7 @@ test('Zibll owns lazySizes while AKSRT consumers share one image-attribute bridg
   assert.doesNotMatch(widgets, /IntersectionObserver/);
 });
 
-test('post lists have no second lazy switch and keep Zibll fallback thumbnails', () => {
+test('post lists have no second lazy switch and keep legacy fallback thumbnails', () => {
   const config = read('inc/helpers/posts-renderer/config.php');
   const postData = read('inc/helpers/posts-renderer/post-data.php');
   const markup = read('inc/helpers/posts-renderer/markup.php');