feat(init): 添加 Linux 系统初始化脚本

- 新增 linux.sh 脚本，用于通用 Linux 系统的初始化
- 添加 README.md 文件，说明脚本功能和使用方法
-脚本功能包括：
  - 更换软件源为清华大学源
  - 设置 DNS 为 114.114.114.114 和 223.5.5.5
  - 设置时区为 Asia/Shanghai 并同步时间
- 支持 Debian、Ubuntu、CentOS、Fedora 等主流 Linux 发行版

init/linux.sh

@@ -0,0 +1,117 @@
+#!/bin/bash
+
+set -euo pipefail
+
+echo "=== 通用 Linux 初始化脚本 ==="
+
+# 确保为 root
+if [ "$EUID" -ne 0 ]; then
+    echo "请以 root 用户运行此脚本。" >&2
+    exit 1
+fi
+
+# 检测系统信息
+get_os_info() {
+    if [ -f /etc/os-release ]; then
+        . /etc/os-release
+        DISTRO_ID=$ID
+        DISTRO_NAME=$NAME
+        DISTRO_VERSION=$VERSION_ID
+    else
+        echo "无法识别系统类型。" >&2
+        exit 1
+    fi
+}
+
+# 设置 DNS
+set_dns() {
+    echo "设置 DNS..."
+    rm -f /etc/resolv.conf
+    cat > /etc/resolv.conf <<EOF
+nameserver 114.114.114.114
+nameserver 223.5.5.5
+EOF
+    if command -v chattr &>/dev/null; then
+        chattr +i /etc/resolv.conf || echo "警告: 无法锁定 resolv.conf"
+    fi
+}
+
+# 设置时区和时间同步
+set_timezone_and_time() {
+    echo "设置时区为 Asia/Shanghai..."
+    timedatectl set-timezone Asia/Shanghai 2>/dev/null || ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
+
+    echo "安装 ntpdate..."
+    $INSTALL_CMD ntpdate -y
+    echo "正在同步时间..."
+    ntpdate ntp.aliyun.com || echo "时间同步失败，请检查网络连接"
+}
+
+# 设置清华源
+set_mirrors() {
+    echo "更换软件源为清华镜像..."
+
+    case "$DISTRO_ID" in
+        debian|ubuntu|raspbian)
+            CODENAME=$(lsb_release -cs 2>/dev/null || echo "stable")
+            cat > /etc/apt/sources.list <<EOF
+deb https://mirrors.tuna.tsinghua.edu.cn/${DISTRO_ID}/ ${CODENAME} main contrib non-free non-free-firmware
+deb https://mirrors.tuna.tsinghua.edu.cn/${DISTRO_ID}/ ${CODENAME}-updates main contrib non-free non-free-firmware
+deb https://mirrors.tuna.tsinghua.edu.cn/${DISTRO_ID}/ ${CODENAME}-backports main contrib non-free non-free-firmware
+deb https://mirrors.tuna.tsinghua.edu.cn/${DISTRO_ID}-security ${CODENAME}-security main contrib non-free non-free-firmware
+EOF
+            apt update -y
+            ;;
+
+        centos|rhel|almalinux|rocky)
+            if [ -f /etc/yum.repos.d/CentOS-Base.repo ]; then
+                cp /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak
+            fi
+            # shellcheck disable=SC2046
+            curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.tuna.tsinghua.edu.cn/help/centos/?date=$(date +%Y%m%d)
+            yum clean all && yum makecache
+            ;;
+
+        fedora)
+            dnf install -y dnf-plugins-core
+            sed -i 's|^metalink=|#metalink=|g' /etc/yum.repos.d/fedora*.repo
+            sed -i 's|^#baseurl=http.*|baseurl=https://mirrors.tuna.tsinghua.edu.cn/fedora/linux/releases/$releasever/Everything/$basearch/os/|g' /etc/yum.repos.d/fedora.repo
+            dnf makecache
+            ;;
+
+        *)
+            echo "不支持的系统: $DISTRO_NAME"
+            exit 1
+            ;;
+    esac
+}
+
+# 主程序
+get_os_info
+
+echo "检测到系统: $DISTRO_NAME $DISTRO_VERSION"
+
+# 判断使用哪个包管理器
+if command -v apt &>/dev/null; then
+    INSTALL_CMD="apt install -y"
+    apt update -y
+elif command -v dnf &>/dev/null; then
+    INSTALL_CMD="dnf install -y"
+    dnf makecache
+elif command -v yum &>/dev/null; then
+    INSTALL_CMD="yum install -y"
+    yum makecache
+else
+    echo "不支持的包管理器。" >&2
+    exit 1
+fi
+
+# 安装通用工具
+$INSTALL_CMD curl wget lsb-release || true
+
+# 执行配置步骤
+set_mirrors
+set_dns
+set_timezone_and_time
+
+echo "=== 初始化完成！系统已优化 ==="