feat: add __main__ module

Added a __main__ module that calls the CLI main function.

src/jcloud_docsgen/__main__.py

@@ -0,0 +1,19 @@
+# Copyright 2026 jCloud
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+#     http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import sys
+from .cli.cli import main
+
+if __name__ == '__main__':
+    sys.exit(main())