Greptile Summary

This PR contains two independent but well-targeted fixes: (1) reduces the Feishu streaming card print_step from 2 to 1 to eliminate client-side visual duplication during live card updates, and (2) updates readSystemctlDetail in the systemd helper to combine both stderr and stdout (rather than silently preferring stderr), fixing an edge case where systemctl is-enabled reports a unit state via stdout while stderr holds a generic error string, which previously caused isSystemdServiceEnabled to throw instead of returning false.

• extensions/feishu/src/streaming-card.ts: print_step.default lowered from 2 → 1; no other changes.
• src/daemon/systemd.ts: readSystemctlDetail now joins stderr and stdout with "\n" so downstream keyword checks (not-found, disabled, etc.) are applied against the full combined output.
• src/daemon/systemd.test.ts: Adds a regression test validating the stdout-carries-state / stderr-carries-generic-error scenario.

Confidence Score: 5/5

• This PR is safe to merge — both changes are minimal, well-understood, and covered by tests.
• The Feishu change is a single integer value tweak in a config struct with no side-effects beyond reduced render step size. The systemd change is a small, well-tested utility function fix whose impact is limited to combining two output streams before keyword matching; the new test directly exercises the previously-broken code path, and existing tests continue to pass. No new dependencies, no API surface changes, no error-handling regressions.
• No files require special attention.

_{Last reviewed commit: ce4a6cc}