feat(lib): add core kazari functions

src/tanabata/kazari.c

@@ -0,0 +1,9 @@
+#include "../../include/tanabata.h"
+
+int tanabata_kazari_add(Tanabata *tanabata, uint64_t sasa_id, uint64_t tanzaku_id) {
+    return kazari_add(&tanabata->shoppyou, sasa_id, tanzaku_id);
+}
+
+int tanabata_kazari_rem(Tanabata *tanabata, uint64_t sasa_id, uint64_t tanzaku_id) {
+    return kazari_rem(&tanabata->shoppyou, sasa_id, tanzaku_id);
+}