feat: add build numbering

kernel/src/Api/BuildNo.hpp

@@ -0,0 +1,15 @@
+/*
+    * BuildNo.hpp
+    * Monotonic kernel build number.
+    *
+    * This file is the source of truth for the build number. It is regenerated
+    * (incremented) by scripts/bump-build.sh whenever the kernel or userspace
+    * sources change, via a rule in kernel/GNUmakefile. Do not edit the number
+    * by hand; the build system manages it.
+    *
+    * Copyright (c) 2026 Daniel Hammer
+*/
+
+#pragma once
+
+#define MONTAUK_BUILD_NUMBER 1