Replace threading.Lock with cython.pymutex and upgrade Cython to 3.2.4

Made-with: Cursor

ai_availability_status.pxd

@@ -7,10 +7,12 @@ cdef enum AIAvailabilityEnum:
     WARNING = 300
     ERROR = 500
 
+from cython cimport pymutex
+
 cdef class AIAvailabilityStatus:
     cdef int status
     cdef str error_message
-    cdef object _lock
+    cdef pymutex _lock
 
     cdef bytes serialize(self)
     cdef set_status(self, int status, str error_message=*)