Hotfix bdf recording (#444)

* change depricated function

* Flush EDF buffer at quarter-second intervals

Reduce the threshold for writing EDF samples from _fs to _fs // 4 so buffered data is flushed more frequently. Previously the FileRecorder only wrote when the buffer exceeded one second of samples; this change triggers writes at roughly quarter-second increments to lower memory usage and latency while retaining the existing behavior of writing full _fs-sized chunks and updating annotations/timestamps under the same lock.

Author: salman2135

src/explorepy/tools.py

@@ -362,7 +362,7 @@ def _write_edf(self, packet):
         self._data = np.concatenate((self._data, data), axis=1)
         self._timestamps += list(data[0, :])
         with lock:
-            if self._data.shape[1] > self._fs:
+            if self._data.shape[1] > self._fs // 4:
                 self._file_obj.writeSamples(list(self._data[:, :self._fs]))
                 self._write_edf_anno()
                 self._data = self._data[:, self._fs:]