Refactor: Update git-committer model to Gemini Flash Lite Preview #3976

Job	Run time
build-and-check	2m 17s
test-.agents	58s
test-backend	39s
test-cli	34s
test-integration-.agents	30s
test-packages/agent-runtime	42s
test-npm-app	35s
test-common	37s
test-integration-common	33s
test-integration-cli	35s
test-integration-web	33s
test-integration-backend	35s
test-integration-packages/agent-runtime	32s
test-integration-npm-app	29s
test-web	28s
	10m 37s

Provide feedback