perf(ci): release coordinator builder executor

scripts/controller-pipeline-contract.test.mjs

@@ -5,9 +5,12 @@ import test from 'node:test'
 const pipeline = (await readFile(new URL('../Jenkinsfile', import.meta.url), 'utf8'))
   .replaceAll('\r\n', '\n')
 
-test('coordinator runs only on the shared Java builder pool', () => {
+test('coordinator releases its builder while waiting for downstream jobs', () => {
+  assert.match(pipeline, /pipeline \{[\s\S]*?agent none/)
+  assert.match(pipeline, /stage\('确定构建范围'\) \{[\s\S]*?agent \{ label 'java-builder' \}/)
   assert.match(pipeline, /agent \{ label 'java-builder' \}/)
   assert.doesNotMatch(pipeline, /agent any/)
+  assert.doesNotMatch(pipeline, /post \{\s*always \{ cleanWs[\s\S]*?\}\s*\}\s*\}\s*$/)
 })
 
 test('AUTO detects database migrations without expanding them to all services', () => {