refactor: split workflow rpc transport by domain

tests/wf_transport_rpc_http/test_structure.py

@@ -0,0 +1,24 @@
+from __future__ import annotations
+
+import importlib
+from pathlib import Path
+
+
+def test_rpc_transport_has_domain_method_modules() -> None:
+    for module_name in (
+        "wf_transport_rpc_http.methods_capabilities",
+        "wf_transport_rpc_http.methods_drafts",
+        "wf_transport_rpc_http.methods_artifacts",
+        "wf_transport_rpc_http.methods_deployments",
+        "wf_transport_rpc_http.methods_runs",
+    ):
+        module = importlib.import_module(module_name)
+
+        assert hasattr(module, "register_methods")
+
+
+def test_rpc_transport_client_stays_thin() -> None:
+    client_path = Path("src/wf_transport_rpc_http/client.py")
+    line_count = len(client_path.read_text(encoding="utf-8").splitlines())
+
+    assert line_count < 140