Phase 5: scaffold Crucible (sow-tools) — dispatcher + builder shims, container, PR-first CI, fail-closed (D11, D19).

internal/buildinfo/buildinfo.go

@@ -0,0 +1,33 @@
+// Package buildinfo reports the Crucible build version.
+//
+// Version is empty in plain `go build`; the build scripts and Dockerfile inject
+// the short git sha via -ldflags. As a fallback we read the VCS revision that
+// the Go toolchain stamps into the binary, so a binary built without -ldflags
+// still self-identifies.
+package buildinfo
+
+import "runtime/debug"
+
+// Version is overridable at link time:
+//
+//	-ldflags "-X gitea.westgate.pw/ShadowsOverWestgate/sow-tools/internal/buildinfo.Version=<sha>"
+var Version = ""
+
+// String returns a human-readable version line, e.g. "crucible 8f31c2a".
+func String() string {
+	return "crucible " + revision()
+}
+
+func revision() string {
+	if Version != "" {
+		return Version
+	}
+	if bi, ok := debug.ReadBuildInfo(); ok {
+		for _, s := range bi.Settings {
+			if s.Key == "vcs.revision" && s.Value != "" {
+				return s.Value
+			}
+		}
+	}
+	return "devel"
+}