Add --host CLI option

So that the service can listen on other addresses than localhost.
This is especially relevant for running as a podman container.

Signed-off-by: Jörn Bethune <jörn@nospam.example.org>

server/dearmep/cli/serve.py

@@ -26,6 +26,7 @@ def serve(ctx: Context) -> None:
         "dearmep.main:create_app",
         factory=True,
         port=ctx.args.port,
+        host=ctx.args.host,
         reload=ctx.args.reload,
         reload_excludes=["node_modules"],  # TODO: doesn't seem to be working
         log_config=ctx.args.log_config,
@@ -57,6 +58,13 @@ def add_parser(
         help=f"TCP port number to use (default: {DEFAULT_PORT})",
     )
 
+    parser.add_argument(
+        "--host",
+        type=str,
+        default="localhost",
+        help="local address on which the service listens",
+    )
+
     parser.add_argument(
         "--reload",
         action="store_true",