refactor(vitepress): 优化 TypeScript 类型与模块导入

- 统一使用 type 导入 TypeScript 类型
- 明确为 .js 文件添加后缀，提升兼容性
- 增加类型注解，提升代码可读性与安全性
- 优化 nullish 合并与可选链写法
- package.json 增加 "type": "module" 字段
- 规范 DefaultTheme 扩展方式，使用 satisfies Theme

Author: jinzhongjia

course/.vitepress/config.mts

@@ -1,6 +1,6 @@
 import { defineConfig } from "vitepress";
 
-import themeConfig from "./themeConfig";
+import themeConfig from "./themeConfig.js";
 
 export default defineConfig({
   lang: "zh-CN",

course/.vitepress/nav.ts

@@ -1,4 +1,4 @@
-import { DefaultTheme } from "vitepress";
+import type { DefaultTheme } from "vitepress";
 
 export default [
   { text: "主页", link: "/" },

course/.vitepress/sidebar.ts

@@ -1,4 +1,4 @@
-import { DefaultTheme } from "vitepress";
+import type { DefaultTheme } from "vitepress";
 
 export default [
   {

course/.vitepress/socialLinks.ts

@@ -1,4 +1,4 @@
-import { DefaultTheme } from "vitepress";
+import type { DefaultTheme } from "vitepress";
 
 export default [
   { icon: "github", link: "https://github.com/zigcc/zig-course" },

course/.vitepress/theme/config.ts

@@ -1,3 +1,3 @@
-const version = "0.14.0";
+const version: string = "0.14.0";
 
 export { version };

course/.vitepress/theme/giscus.ts

@@ -3,17 +3,14 @@ import { defineComponent, h } from "vue";
 import { useData, useRoute } from "vitepress";
 import Giscus from "@giscus/vue";
 
-const is_dev = process.env.NODE_ENV === "development";
+const is_dev: boolean = process.env.NODE_ENV === "development";
 
 export default defineComponent({
   setup() {
     const { isDark, title, frontmatter } = useData();
 
     return () =>
-      is_dev ||
-      !(typeof frontmatter.value.comments == "undefined"
-        ? true
-        : frontmatter.value.comments)
+      is_dev || !(frontmatter.value.comments ?? true)
         ? h("div")
         : h(
             "div",

course/.vitepress/theme/index.ts

@@ -1,14 +1,15 @@
-// .vitepress/theme/index.js
+// .vitepress/theme/index.ts
+import type { Theme } from "vitepress";
 import DefaultTheme from "vitepress/theme";
 
-import giscus from "./giscus";
-import version from "./version";
+import giscus from "./giscus.js";
+import version from "./version.js";
 import "./style/print.css";
 
 import { h } from "vue";
 
 export default {
-  ...DefaultTheme,
+  extends: DefaultTheme,
   enhanceApp(ctx: any) {
     DefaultTheme.enhanceApp(ctx);
     if (typeof window != "undefined") {
@@ -33,4 +34,4 @@ export default {
       "doc-before": () => h(version),
     });
   },
-};
+} satisfies Theme;

course/.vitepress/theme/version.ts

@@ -1,17 +1,18 @@
 import { defineComponent, h, ref, computed } from "vue";
+import type { Ref, ComputedRef } from "vue";
 
 import { useData } from "vitepress";
-import { version } from "./config";
+import { version } from "./config.js";
 
 export default defineComponent({
   setup() {
     const { isDark, frontmatter } = useData();
 
-    const currentVersion = ref(version);
+    const currentVersion: Ref<string> = ref(version);
 
-    const fontColor = computed(() => (isDark.value ? "#fff" : "#000"));
+    const fontColor: ComputedRef<string> = computed(() => (isDark.value ? "#fff" : "#000"));
 
-    const backgroundColor = computed(() =>
+    const backgroundColor: ComputedRef<string> = computed(() =>
       isDark.value ? "#14120F" : "#ebedf0",
     );
 

course/.vitepress/themeConfig.ts

@@ -1,7 +1,7 @@
-import { DefaultTheme } from "vitepress";
-import sidebar from "./sidebar";
-import nav from "./nav";
-import socialLinks from "./socialLinks";
+import type { DefaultTheme } from "vitepress";
+import sidebar from "./sidebar.js";
+import nav from "./nav.js";
+import socialLinks from "./socialLinks.js";
 
 const config: DefaultTheme.Config = {
   editLink: {

course/.vitepress/vitepress-pdf.config.ts

@@ -2,11 +2,11 @@
 import type { DefaultTheme } from "vitepress";
 import { defineUserConfig } from "vitepress-export-pdf";
 
-import sidebar from "./sidebar";
+import sidebar from "./sidebar.js";
 
-let links: string[] = [];
+const links: string[] = [];
 
-function ExtractLinks(item: DefaultTheme.SidebarItem) {
+function ExtractLinks(item: DefaultTheme.SidebarItem): void {
   if (item.link) {
     if (item.link === "/") {
       // 此处额外打了一个补丁，因为首页的链接是 /index
@@ -16,10 +16,11 @@ function ExtractLinks(item: DefaultTheme.SidebarItem) {
     }
   }
 
-  if (item.items)
+  if (item.items) {
     for (const key in item.items) {
       ExtractLinks(item.items[key]);
     }
+  }
 }
 
 for (const key in sidebar) {