Separate CLI client/server deps

Author: padraic-shafer

tiled/commandline/_serve.py

@@ -5,8 +5,6 @@
 
 import typer
 
-from tiled.server.settings import get_settings
-
 serve_app = typer.Typer(no_args_is_help=True)
 
 SQLITE_CATALOG_FILENAME = "catalog.db"
@@ -194,6 +192,10 @@ def serve_directory(
     if api_key is None:
         api_key = os.getenv("TILED_SINGLE_USER_API_KEY")
         if api_key is None:
+            # Lazily import server settings here to avoid server dependencies
+            # in client-only environments.
+            from tiled.server.settings import get_settings
+
             api_key = get_settings().single_user_api_key
             generated = True