Add a fallback logger

Fixes fi3ework#238

It appears `config.logger` can be null or undefined,
despite the typescript types for Vite specifying
logger as required

packages/vite-plugin-checker/src/main.ts

@@ -23,6 +23,7 @@ import {
   type UserPluginConfig,
 } from './types.js'
 import type { ConfigEnv, Plugin, Logger } from 'vite'
+import { createLogger } from 'vite'
 
 const buildInCheckerKeys: BuildInCheckerNames[] = [
   'typescript',
@@ -96,7 +97,11 @@ export function checker(userConfig: UserPluginConfig): Plugin {
       })
     },
     configResolved(config) {
-      logger = config.logger
+      if (config.logger) {
+        logger = config.logger
+      } else {
+        logger = createLogger()
+      }
       baseWithOrigin = config.server.origin ? config.server.origin + config.base : config.base
       isProduction ||= config.isProduction || config.command === 'build'
       buildWatch = !!config.build.watch