feat(sessions): add resuming to geminiChat and add CLI flags for session management (#10719)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

packages/cli/src/nonInteractiveCli.test.ts

@@ -93,6 +93,7 @@ describe('runNonInteractive', () => {
   let processStderrSpy: MockInstance;
   let mockGeminiClient: {
     sendMessageStream: Mock;
+    resumeChat: Mock;
     getChatRecordingService: Mock;
   };
   const MOCK_SESSION_METRICS: SessionMetrics = {
@@ -142,6 +143,7 @@ describe('runNonInteractive', () => {
 
     mockGeminiClient = {
       sendMessageStream: vi.fn(),
+      resumeChat: vi.fn().mockResolvedValue(undefined),
       getChatRecordingService: vi.fn(() => ({
         initialize: vi.fn(),
         recordMessage: vi.fn(),