fix: use forkserver as process start method

Signed-off-by: Anupam Kumar <kyteinsky@gmail.com>

Author: kyteinsky

main.py

@@ -3,6 +3,19 @@
 # SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
 # SPDX-License-Identifier: AGPL-3.0-or-later
 #
+
+import multiprocessing as mp
+
+# do forks from a clean process that doesn't have any threads or locks
+mp.set_start_method('forkserver')
+mp.set_forkserver_preload([
+	'langchain',
+	'sqlalchemy',
+	'numpy',
+	'context_chat_backend.chain.ingest.injest',
+	'context_chat_backend.vectordb.pgvector',
+])
+
 import logging
 from os import cpu_count, getenv