feat(runtime): 全站前端脚本统一接入 AksrtFrontend 全局 DOM 生命周期

- rehydrate.js 新增 boot()/aksrt:ready 事件，支持 boot 后晚注册立即以 init 触发
- aksrt-runtime.js 初始加载改走 AksrtFrontend.boot，tooltip/倒计时注册为组件
- 约 30 个前端脚本（首页、评论、支付、路由、页面叶子、widgets）
  从直接 DOMContentLoaded 迁移为 AksrtFrontend.register，并加幂等标记
- section-navs 依赖改为 aksrt-runtime，保证注册时序
- 清理死代码：删除孤儿 loader.js/main.js 及 runtime/page-navs 遗留副本
- loader.js 移除已迁移模块的 tbquire 路径映射，main.js 相应瘦身
- build-public-assets.mjs 增加 runtime/main.min.js 自动压缩步骤
- 新增 4 个契约测试（homepage-dom/rehydrate-runtime/global-dom-init/
  public-bundle-parity），3 个既有 harness 适配注册表初始化方式

tests/widget-system/homepage-dom-contract.test.cjs

@@ -0,0 +1,85 @@
+'use strict';
+
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const vm = require('node:vm');
+const test = require('node:test');
+
+const root = path.resolve(__dirname, '..', '..');
+const read = (file) => fs.readFileSync(path.join(root, file), 'utf8');
+
+test('homepage uses the global DOM lifecycle without a second ready path', () => {
+  const runtime = read('assets/js/aksrt-runtime.js');
+  const homepage = read('assets/js/homepage-fixed.js');
+
+  assert.match(runtime, /aksrt\.autoFun\s*=\s*function\s*\(root, reason\)/);
+  assert.match(runtime, /function initRuntime\(\)\s*\{\s*aksrt\.autoFun\(document, 'init'\);/s);
+  assert.doesNotMatch(runtime, /function initRuntime\(\)\s*\{\s*aksrt\.autoFun\(document\);/s);
+
+  assert.match(homepage, /window\.AksrtFrontend\.register\('aksrt-homepage', init\)/);
+  assert.doesNotMatch(homepage, /DOMContentLoaded/);
+  assert.doesNotMatch(homepage, /document\.querySelectorAll\('\[data-sort-dropdown-trigger\]'\)/);
+  assert.doesNotMatch(homepage, /document\.querySelectorAll\('\.aksrt-homepage__stream'\)/);
+  assert.doesNotMatch(homepage, /document\.querySelectorAll\('\.aksrt-homepage__tabs\.home-tab-nav-box'\)/);
+  assert.match(homepage, /dataset\.aksrtHomeTabsBound === '1'/);
+  assert.match(homepage, /dataset\.aksrtSortDropdownBound === '1'/);
+  assert.match(homepage, /dataset\.aksrtSortbarBound === '1'/);
+  assert.match(homepage, /dataset\.aksrtStickyTabsBound === '1'/);
+});
+
+test('homepage initializer is registered once and remains idempotent across rehydrate calls', () => {
+  const source = read('assets/js/homepage-fixed.js');
+  const registrations = [];
+  let sortbarClickBindings = 0;
+  const sortbar = {
+    dataset: {},
+    getAttribute() {
+      return null;
+    },
+    addEventListener(type) {
+      if (type === 'click') sortbarClickBindings++;
+    },
+  };
+  const stream = {
+    querySelector(selector) {
+      return selector === '.aksrt-homepage__sortbar' ? sortbar : null;
+    },
+  };
+  const scope = {
+    querySelectorAll(selector) {
+      return selector === '.aksrt-homepage__stream' ? [stream] : [];
+    },
+  };
+  const context = {
+    window: {
+      AksrtFrontend: {
+        register(name, init) {
+          registrations.push({ name, init });
+        },
+      },
+    },
+    document: scope,
+    console,
+    URLSearchParams,
+    URL,
+    setTimeout,
+    clearTimeout,
+  };
+  context.window.window = context.window;
+  context.window.document = scope;
+  vm.runInNewContext(source, context, { filename: 'homepage-fixed.js' });
+
+  assert.equal(registrations.length, 1);
+  assert.equal(registrations[0].name, 'aksrt-homepage');
+  assert.equal(typeof registrations[0].init, 'function');
+  registrations[0].init(scope, 'init');
+  registrations[0].init(scope, 'ajax');
+  assert.equal(sortbarClickBindings, 1);
+  assert.equal(sortbar.dataset.aksrtSortbarBound, '1');
+});
+
+test('homepage AJAX content continues to use the shared ajax rehydrate contract', () => {
+  const homepage = read('assets/js/homepage-fixed.js');
+  assert.match(homepage, /window\.AksrtFrontend\.rehydrate\(panel, 'ajax'\)/);
+});