docs: added custom logger info (#10108)

Co-authored-by: 翠 / green <[email protected]>
Co-authored-by: bluwy <[email protected]>

docs/config/shared-options.md

@@ -325,6 +325,40 @@ export default defineConfig({
 
 Adjust console output verbosity. Default is `'info'`.
 
+## customLogger
+
+- **Type:**
+  ```ts
+  interface Logger {
+    info(msg: string, options?: LogOptions): void
+    warn(msg: string, options?: LogOptions): void
+    warnOnce(msg: string, options?: LogOptions): void
+    error(msg: string, options?: LogErrorOptions): void
+    clearScreen(type: LogType): void
+    hasErrorLogged(error: Error | RollupError): boolean
+    hasWarned: boolean
+  }
+  ```
+
+Use a custom logger to log messages. You can use Vite's `createLogger` API to get the default logger and customize it to, for example, change the message or filter out certain warnings.
+
+```js
+import { createLogger, defineConfig } from 'vite'
+
+const logger = createLogger()
+const loggerWarn = logger.warn
+
+logger.warn = (msg, options) => {
+  // Ignore empty CSS files warning
+  if (msg.includes('vite:css') && msg.includes(' is empty')) return
+  loggerWarn(msg, options)
+}
+
+export default defineConfig({
+  customLogger: logger,
+})
+```
+
 ## clearScreen
 
 - **Type:** `boolean`