chore: add clang-format config, CI workflow, Makefile, and initial C library source files

rkeytable.c

@@ -0,0 +1,12 @@
+#include "rkeytable.h"
+#include "rtest.h"
+#include "rstring.h"
+
+int main() {
+
+    for (int i = 0; i < 1000; i++) {
+        char *key = rgenerate_key();
+        rkset(key, "tast");
+        rasserts(!strcmp(rkget(key), "tast"));
+    }
+}