test(cli): cover terminal sequence outcomes

[ovasylenko]

Summary

• exercise a successful orch8 dev --once run with mocked output
• verify failed sequences exit nonzero and surface the engine error
• verify --skip-timers fast-forwards a multi-day delay

Verification

• cargo +1.97.0 fmt --check
• cargo +1.97.0 test -p orch8-cli --test cli_e2e
• cargo +1.97.0 clippy -p orch8-cli --tests -- -D warnings