[codex] Add DeepSeek session trace exporter (#707) #750

Job	Run time
build-and-smoke-freebuff-windows	2m 33s
build-freebuff	1m 24s
e2e-agent-startup	2m 9s
e2e-version	50s
e2e-startup	1m 5s
e2e-slash-commands	51s
e2e-code-edit	1m 0s
e2e-ads-behavior	1m 11s
e2e-help-command	1m 16s
e2e-terminal-command	59s
	13m 18s

Provide feedback