feat(deploy): SemVer 版本管理 + 自动化发版流水线

- deploy.yml: tag 触发（v*.*.*），四阶段调脚本（compile/test/release/deploy）
- manual.yml: workflow_dispatch 支持手动回滚，checkout 指定 tag
- scripts/ci/compile.sh: 构建 Go 二进制 + Flutter Web，打包 dist/
- scripts/ci/test.sh: go test + flutter analyze
- scripts/ci/release.sh: 解析 CHANGELOG.md → 更新 version.yaml → 创建 Forgejo Release
- scripts/ci/deploy.sh: 从 Release 下载产物（自动/手动均可）→ 部署到 EC2
- CHANGELOG.md: Keep a Changelog 格式，初始 v1.0.0 条目
- backend: GetRelease 改读 version.yaml，移除 ENV 变量依赖
- backend/config/version.yaml: 重置为 v1.0.0
- web/download.html: 动态拉取 /api/v1/public/release 展示版本号和更新内容

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/download.html

@@ -954,15 +954,15 @@ footer {
     </p>
 
     <div class="changelog">
-      <!-- v1.6.2 -->
+      <!-- 当前版本（由 JS 动态更新） -->
       <div class="changelog-entry current">
         <div class="changelog-meta">
-          <div class="changelog-version">v1.6.2</div>
-          <div class="changelog-date">2026-05-15</div>
+          <div class="changelog-version" id="version-badge">...</div>
+          <div class="changelog-date" id="release-date">-</div>
           <span class="changelog-tag">当前版本</span>
         </div>
         <div class="changelog-body">
-          <h3>多仓库联动盘点与权限增强</h3>
+          <h3 id="release-notes">加载中...</h3>
           <div class="changelog-cat">
             <div class="changelog-cat-label"><span class="dot feature"></span>新功能</div>
             <ul>
@@ -1193,8 +1193,23 @@ function renderNav() {
   if (window.lucide) lucide.createIcons();
 }
 
+function loadReleaseInfo() {
+  fetch('https://jiu.51yanmei.com/api/v1/public/release')
+    .then(function(r) { return r.json(); })
+    .then(function(data) {
+      var badge = document.getElementById('version-badge');
+      var notes = document.getElementById('release-notes');
+      var date  = document.getElementById('release-date');
+      if (badge && data.version) badge.textContent = 'v' + data.version;
+      if (notes && data.release_notes) notes.textContent = data.release_notes;
+      if (date) date.textContent = new Date().toISOString().slice(0, 10);
+    })
+    .catch(function() {});
+}
+
 document.addEventListener('DOMContentLoaded', function() {
   renderNav();
+  loadReleaseInfo();
   if (window.lucide) lucide.createIcons();
 });
 </script>