refactor(cli): reorganize command handling and the dev server lifecycle

The file grew a nested if/else chain with inline command bodies, a dev
path that redefined restartServer inside createDevServer on every server
generation, and a module-level restartPromise shared with it.

Read it top to bottom instead: argv parsing, a flat dispatch chain, then
runDev() owning the dev session — its config, its current server and the
restart de-duplication — with the restart sequence spelled out in order.

No behavior change.

src/node/cli.ts

@@ -1,6 +1,6 @@
 import minimist from 'minimist'
 import c from 'picocolors'
-import { createLogger } from 'vite'
+import { createLogger, type ViteDevServer } from 'vite'
 
 import {
   build,
@@ -16,6 +16,7 @@ import { logVersion } from './utils/logVersion'
 
 const argv: any = minimist(process.argv.slice(2))
 
+// minimist keeps `--flag=true` as the string 'true'
 Object.keys(argv).forEach((key) => {
   if (argv[key] === 'true') {
     argv[key] = true
@@ -24,16 +25,33 @@ Object.keys(argv).forEach((key) => {
   }
 })
 
+// vitepress [command] [root]
 const command = argv._[0]
 const root = argv._[command ? 1 : 0]
 if (root) {
   argv.root = root
 }
 
-let restartPromise: Promise<void> | undefined
-
 if (!command || command === 'dev') {
+  runDev(root, argv).catch(
+    logErrorAndExit.bind(null, `failed to start server. error:`)
+  )
+} else if (command === 'init') {
+  createLogger().info('', { clear: true })
+  init(argv.root)
+} else if (command === 'build') {
+  build(root, argv).catch(logErrorAndExit.bind(null, `build error:`))
+} else if (command === 'serve' || command === 'preview') {
+  serve(argv).catch(
+    logErrorAndExit.bind(null, `failed to start server. error:`)
+  )
+} else {
+  logErrorAndExit(`unknown command "${command}".`)
+}
+
+async function runDev(root: string, argv: any) {
   if (argv.force) {
+    // vite moved --force under optimizeDeps
     delete argv.force
     argv.optimizeDeps = { force: true }
   }
@@ -41,48 +59,41 @@ if (!command || command === 'dev') {
   let config = await resolveConfig(root, argv).catch(
     logErrorAndExit.bind(null, `failed to resolve config. error:`)
   )
-  const createDevServer = async (isRestart = true) => {
-    const server = await createServer(root, argv, restartServer, config)
-    function restartServer() {
-      if (!restartPromise) {
-        restartPromise = (async () => {
-          try {
-            config = await resolveConfig(root, argv)
-          } catch (err: any) {
-            logError(`failed to resolve config. error:`, err)
-            return
-          }
-          disposeMdItInstance()
-          clearCache()
-          await server.close()
-          await createDevServer()
-        })().finally(() => {
-          restartPromise = undefined
-        })
-      }
-      return restartPromise
-    }
+  let server: ViteDevServer
+  let restartPromise: Promise<void> | undefined
+
+  async function startServer(isRestart = true) {
+    server = await createServer(root, argv, restartServer, config)
+    // isRestart keeps vite from reopening the browser
     await server.listen(undefined, isRestart)
     logVersion(server.config.logger)
     server.printUrls()
     bindShortcuts(server, restartServer)
   }
-  createDevServer(false).catch(
-    logErrorAndExit.bind(null, `failed to start server. error:`)
-  )
-} else if (command === 'init') {
-  createLogger().info('', { clear: true })
-  init(argv.root)
-} else {
-  if (command === 'build') {
-    build(root, argv).catch(logErrorAndExit.bind(null, `build error:`))
-  } else if (command === 'serve' || command === 'preview') {
-    serve(argv).catch(
-      logErrorAndExit.bind(null, `failed to start server. error:`)
-    )
-  } else {
-    logErrorAndExit(`unknown command "${command}".`)
+
+  // the config watcher and the r shortcut can both ask at once
+  function restartServer() {
+    restartPromise ??= restart().finally(() => {
+      restartPromise = undefined
+    })
+    return restartPromise
+  }
+
+  async function restart() {
+    try {
+      config = await resolveConfig(root, argv)
+    } catch (err: any) {
+      logError(`failed to resolve config. error:`, err)
+      return
+    }
+
+    disposeMdItInstance()
+    clearCache()
+    await server.close()
+    await startServer()
   }
+
+  await startServer(false)
 }
 
 function logErrorAndExit(message: string, err?: any): never {