refactor(fmt): flatten formatter sources

Author: chenjiahan

packages/rstack/src/fmt/runner.ts

@@ -1,5 +1,5 @@
 import type { FmtExitCode, FmtFileResult, FmtRunResult, RunFmtFilesOptions } from './types.ts';
-import { formatFileSerial } from './vendor/prettier-cli/serial.ts';
+import { formatFileSerial } from './serial.ts';
 
 const runFmtFiles = async ({ files, mode }: RunFmtFilesOptions): Promise<FmtRunResult> => {
   const startTime = performance.now();

…ck/src/fmt/vendor/prettier-cli/serial.ts packages/rstack/src/fmt/serial.tspackages/rstack/src/fmt/vendor/prettier-cli/serial.ts renamed to packages/rstack/src/fmt/serial.ts packages/rstack/src/fmt/vendor/prettier-cli/serial.ts renamed to packages/rstack/src/fmt/serial.ts

@@ -6,7 +6,7 @@
 
 import { readFile, writeFile } from 'atomically';
 import { format } from 'prettier';
-import type { FmtFileRequest } from '../../types.ts';
+import type { FmtFileRequest } from './types.ts';
 
 const formatFileSerial = async (
   { path, options }: FmtFileRequest,