Refactor main() into run() int (main calls os.Exit(run())) so the test
can exercise the CLI directly without os.Exit terminating the test
process. Add main_test.go with two cases: run() success path (version
command → exit 0) and run() error path (job run with missing spec →
exit 1, stderr contains "error:"). Low-effort toe-hold per RESEARCH
§1.1/§1.4 — do not over-invest in glue-code coverage.
Coverage: go test -cover ./cmd/orca → 80.0% (was 0%, target ≥50%).
go test -race PASS.
---ci---
project: orca
phase: 1
milestone: v0.8
status: execute
---/ci---