Add CodeBuddy as a built-in coding agent (#23740)

* feat(agents): integrate CodeBuddy launch, status and session history

* docs: record CodeBuddy lifecycle verification

* fix(codebuddy): backfill scoped history and negotiate remote resume

* test(cli): include CodeBuddy in known search agents

src/shared/codebuddy-headless-command.ts

@@ -0,0 +1,13 @@
+import { agentArgOptionTokens } from './agent-session-option-agent-args'
+import { isPrintModeHeadlessOneShotCommand, optionName } from './print-mode-headless-command'
+
+const NON_INTERACTIVE_FLAGS = new Set(['--serve', '--acp', '--bg', '--background'])
+
+export function isCodebuddyNonInteractiveCommand(tokens: readonly string[]): boolean {
+  return (
+    isPrintModeHeadlessOneShotCommand(tokens) ||
+    agentArgOptionTokens(tokens)
+      .slice(1)
+      .some((token) => NON_INTERACTIVE_FLAGS.has(optionName(token)))
+  )
+}