feat: add sharing API client and server tools

nextcloud_mcp_server/server/__init__.py

@@ -2,6 +2,7 @@ from .calendar import configure_calendar_tools
 from .contacts import configure_contacts_tools
 from .deck import configure_deck_tools
 from .notes import configure_notes_tools
+from .sharing import configure_sharing_tools
 from .tables import configure_tables_tools
 from .webdav import configure_webdav_tools
 
@@ -10,6 +11,7 @@ __all__ = [
     "configure_contacts_tools",
     "configure_deck_tools",
     "configure_notes_tools",
+    "configure_sharing_tools",
     "configure_tables_tools",
     "configure_webdav_tools",
 ]