Initial commit: full Phases 1-6 implementation

Post-repair hardware validation pipeline for Proxmox cluster hosts.
Go orchestrator + in-image agent + mkosi live image + bundled dnsmasq
PXE + SQLite + HTMX/SSE UI + notify registry + janitor + full docs.

internal/orchestrator/wol_test.go

@@ -0,0 +1,37 @@
+package orchestrator
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestParseMAC(t *testing.T) {
+	got, err := parseMAC("aa:bb:cc:dd:ee:ff")
+	if err != nil {
+		t.Fatalf("parseMAC: %v", err)
+	}
+	want := []byte{0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff}
+	if !bytes.Equal(got, want) {
+		t.Fatalf("parseMAC: %x != %x", got, want)
+	}
+}
+
+func TestParseMACUpper(t *testing.T) {
+	// Must be case-insensitive so users can paste either form.
+	got, err := parseMAC("AA:BB:CC:DD:EE:FF")
+	if err != nil {
+		t.Fatalf("parseMAC upper: %v", err)
+	}
+	want := []byte{0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff}
+	if !bytes.Equal(got, want) {
+		t.Fatalf("parseMAC upper: %x != %x", got, want)
+	}
+}
+
+func TestParseMACInvalid(t *testing.T) {
+	for _, bad := range []string{"", "aa:bb:cc", "zz:yy:xx:ww:vv:uu", "aa-bb-cc-dd-ee-ff", "aa:bb:cc:dd:ee:ff:00"} {
+		if _, err := parseMAC(bad); err == nil {
+			t.Errorf("expected error for %q", bad)
+		}
+	}
+}