Add VitePress configuration for Crystal project docs

Introduced a VitePress configuration file to set up documentation for the Crystal project:
- Configured project title and description
- Implemented MiniSearch for enhanced search functionality
- Dynamically generated sidebar and navigation based on sidebar content
- Added custom theme settings, including search and outline preferences

This configuration aids in maintaining organized and easily navigable documentation.

vitepress/docs/.vitepress/config.js

@@ -0,0 +1,98 @@
+import { fileURLToPath } from 'url'
+import { dirname, join, parse } from 'path';
+import { readdirSync, readFileSync } from "fs"
+import { defineConfig } from 'vitepress'
+import MiniSearch from 'minisearch'
+
+const splitter = "+++"
+const sidebar_folder = join(dirname(fileURLToPath(import.meta.url)), "crystal")
+const sidebars = readdirSync(sidebar_folder)
+const sidebars_json = {}
+
+sidebars.forEach(x => {
+  let [name, version] = x.split(splitter)
+  version = parse(version).name
+
+  const raw = readFileSync(join(sidebar_folder, x), { encoding: "utf-8" })
+
+  sidebars_json[version] = {
+    name,
+    json: JSON.parse(raw)
+  }
+})
+// NOTE: Above code imports all sidebars.
+
+export default defineConfig({
+  title: 'Cql Documentation',
+  // TODO: Change me.
+  description: 'My awesome Crystal project!',
+  lastUpdated: true,
+  ignoreDeadLinks: true,
+  base: '/cql/',
+  themeConfig: {
+    search: {
+      provider: 'minisearch',
+      options: {
+        // MiniSearch-specific options
+        fields: ['title', 'description', 'content'], // fields to index
+        storeFields: ['title', 'description'], // fields to store for display
+        searchOptions: {
+          boost: { title: 2 }, // boost title relevance in search
+          prefix: true, // allow matching by prefix
+          fuzzy: 0.2 // set fuzzy search tolerance
+        }
+      }
+    },
+    outline: {
+      level: [2, 6], // Specifies which header levels to include in the TOC (e.g., from <h2> to <h6>)
+      label: 'On this page' // Custom label for the outline
+    },
+    nav: [
+      nav()
+    ],
+    sidebar: sidebar(),
+    socialLinks: [
+      { icon: 'github', link: 'https://github.com/azutoolkit/cql' }
+    ]
+  }
+})
+
+// NOTE: below code creates the sidebar and navbar
+// based on the amount of sidebars and their contents.
+function sidebar() {
+  result = {}
+
+  for (const [key, value] of Object.entries(sidebars_json)) {
+    result[key] = [
+      {
+        text: "Cql API",
+        items: value.json
+      }
+    ]
+  }
+
+  return result
+}
+
+function nav() {
+  if (Object.keys(sidebars_json).length === 1) {
+    return {
+      text: 'Cql API',
+      link: `${Object.values(sidebars_json)[0].json[0].link}`
+    }
+  }
+
+  result = {
+    text: 'Version',
+    items: []
+  }
+
+  for (const [key, value] of Object.entries(sidebars_json)) {
+    result.items.push({
+      text: `${key}`,
+      link: `${value.json[0].link}`
+    })
+  }
+
+  return result
+}