oops many changes

include/user_config.h

@@ -0,0 +1,18 @@
+#ifndef KEYVIBE_CONFIG_IO_H
+#define KEYVIBE_CONFIG_IO_H
+#include <stddef.h>
+
+// Resolve user config path: returns buffer on success, NULL on failure
+char *get_user_config_path(char *buffer, size_t buflen);
+
+// Write ~/.keyvibe.json in new format
+int write_user_config(const char *path, const char *keyboard_sound,
+                      const char *mouse_sound, int keyboard_volume,
+                      int mouse_volume);
+
+// Read ~/.keyvibe.json supporting new and legacy formats
+int read_user_config(const char *path, char **out_keyboard_sound,
+                     char **out_mouse_sound, int *out_keyboard_volume,
+                     int *out_mouse_volume);
+
+#endif // KEYVIBE_CONFIG_IO_H