feat: add git post-receive hook for auto build and start

Adds a `git_hooks/post-receive` script that runs `pnpm run build:start`
(equivalent to `next build && next start`) automatically after a push is
received, enabling deployment on `receive.denyCurrentBranch=updateInstead`
configured repos (e.g., production/test servers).

Updates the README with a new "Git Hooks" section explaining:

- How to enable the hooks locally via `git config core.hooksPath git_hooks`
- That `core.hooksPath` is a local config and must be set per clone
- That `post-receive` fires on the receiving (push target) machine, not
  the local dev machine

README.md

@@ -20,6 +20,28 @@ You can start editing the page by modifying `app/page.tsx`. The page auto-update
 
 This project uses [`next/font`](https://nextjs.org/docs/app/building-your-application/optimizing/fonts) to automatically optimize and load [Geist](https://vercel.com/font), a new font family for Vercel.
 
+## Git Hooks
+
+项目使用 `git_hooks/` 目录存放**仓库内**的 git hooks（**不**在 `.git/hooks/`）。**clone 后需手动启用**：
+
+```bash
+git config core.hooksPath git_hooks
+```
+
+### 启用的 Hook
+
+#### `post-receive`
+
+**触发场景**：`git push` 到本仓库时（在 **bare repo** 或 `receive.denyCurrentBranch=updateInstead` 的非 bare repo 上）。
+
+**行为**：自动执行 `pnpm run build:start`，即 `next build && next start`。
+
+**注意事项**：
+
+- 本仓库的 `git_hooks/post-receive` **不**会**自动**生效 —— 必须在每个工作副本上跑一次上面的 `git config` 命令
+- `core.hooksPath` 是**本地** git config（写入 `.git/config`），**不**随仓库提交
+- `post-receive` 在**接收端**触发 —— 即 push 目标机器（生产 / 测试服务器）的 hook，不是本地开发机的
+
 ## Learn More
 
 To learn more about Next.js, take a look at the following resources:

git_hooks/post-receive

@@ -0,0 +1,11 @@
+#!/bin/sh
+# Post-receive hook: push 后自动 build + start
+#
+# 触发场景：
+#   - 非 bare repo + receive.denyCurrentBranch=updateInstead：本地推送自动部署
+#
+# 用途：执行 package.json 中的 `build:start` 脚本
+#   - 内部 = `npm run build && npm run start`
+#   - 实际调用 `pnpm run build:start`（项目使用 pnpm）
+
+pnpm run build:start