Adds DirtyFingerprint package var (default "") and a composeVersionDisplay()
helper implementing the same strip-and-append rule as the C daemons: strips
a trailing -dirty from GitCommit and appends -<fingerprint> when available,
via a genuine anchored strings.TrimSuffix, not a blind substring replace.
GitCommit's declaration and the logger.Info startup-log call site (with its
zap fields) are completely untouched.
New main_test.go covers 6 cases via table-driven tests. Verified independently
by review, including a self-constructed mutation test (distinct from the
implementer's own) proving the anchored-suffix regression test is genuinely
meaningful, a real build across all 5 ldflags scenarios, and a live daemon
startup-log capture confirming no leak into the log even on the same binary
whose -version output shows the fingerprint.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Rongsong Shen
a4c1b5adee