feat: contact form backend for linux and freebsd servers

Assisted-by: GLM 5.3 Flash

internal/version/version.go

@@ -0,0 +1,25 @@
+// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
+// SPDX-License-Identifier: MIT
+
+//go:build linux || freebsd
+
+// Package version exposes the nuntius release identity.
+package version
+
+import "runtime/debug"
+
+// Name is the program name reported by `--version` and in log lines.
+const Name = "nuntius"
+
+// Version reports the release the toolchain recorded for this build: the
+// tag when the checkout is at one, a pseudo-version naming the commit
+// otherwise, and (devel) outside version control. Nothing writes a version
+// number, so the recorded value cannot go stale, and a dirty tree reports
+// +dirty honestly.
+func Version() string {
+	bi, ok := debug.ReadBuildInfo()
+	if !ok || bi.Main.Version == "" {
+		return "(devel)"
+	}
+	return bi.Main.Version
+}

internal/version/version_test.go

@@ -0,0 +1,22 @@
+// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
+// SPDX-License-Identifier: MIT
+
+//go:build linux || freebsd
+
+package version
+
+import "testing"
+
+func TestName(t *testing.T) {
+	if Name != "nuntius" {
+		t.Errorf("Name = %q, want %q", Name, "nuntius")
+	}
+}
+
+func TestVersion(t *testing.T) {
+	// The recorded version is never empty: at a tag it is the tag, elsewhere
+	// a pseudo-version, and (devel) outside version control.
+	if Version() == "" {
+		t.Error("Version must not be empty")
+	}
+}