refactoring; finishing integration of CMocka; several test cases covered

src/db/CMakeLists.txt

@@ -5,11 +5,15 @@ if (USE_POSTGRESQL)
     target_link_libraries(db
         PRIVATE
             PostgreSQL::PostgreSQL
+            main
+            utils
     )
 else()
     target_link_libraries(db
         PRIVATE
             SQLite3::SQLite3
+            main
+            utils
     )
 endif()
 

src/db/db_sqlite.c

@@ -1,8 +1,8 @@
 /* SPDX-License-Identifier: MIT */
 /* Copyright (c) 2026 Oleksandr Zhylin */
 
-#include "../main.h"
-#include "../utils.h"
+#include <main.h>
+#include <utils.h>
 #include "db_common.h"
 #include <db.h>
 #include <endian.h>