common: Add trace.h header

Signed-off-by: Ian Moffett <ian@mirocom.org>

include/common/trace.h

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2026, Mirocom Laboratories
+ * Provided under the BSD-3 clause
+ *
+ * Abstract:
+ *      This header provides trace helpers.
+ * Author:
+ *      Ian M. Moffett <ian@mirocom.org>
+ */
+
+#ifndef COMMON_TRACE_H
+#define COMMON_TRACE_H 1
+
+#include <stdio.h>
+#include "common/state.h"
+
+#define trace_error(state, fmt, ...)            \
+    printf("fatal: " fmt, ##__VA_ARGS__);       \
+    printf("near line %d\n", (state)->line_num);
+
+#endif  /* !COMMON_TRACE_H */