fix(mcp): C1 per-verb circuit breaker trips on incomplete_input too

Smoke run 3 showed Main PM hitting 7 incomplete_input rejections on
the decision-note required-fields gate before finally succeeding.
The per-verb breaker tracks repeated rejections of the same verb in
a 60s window and returns circuit_open after the 3rd strike — but its
classification set only included tracing_gap. incomplete_input was
added in Wave 1 (pre-gateway parity for decision/reflect structured
fields) and should have been added to the breaker at the same time.

Spec ref: docs/superpowers/specs/2026-05-12-post-smoke-3-fixes-design.md
section C1.

tests/unit/mcp_servers/test_circuit_incomplete_input.py

@@ -0,0 +1,69 @@
+"""Wave C1: per-verb circuit breaker trips on incomplete_input too.
+
+Smoke run 3 showed Main PM hitting 7 incomplete_input rejections in
+~30 seconds on the decision-note required-fields gate. The breaker
+only included tracing_gap; incomplete_input was added in Wave 1 but
+the breaker classification wasn't updated.
+"""
+
+from __future__ import annotations
+
+import importlib
+import json
+from typing import TYPE_CHECKING
+
+import pytest
+
+if TYPE_CHECKING:
+    import types
+    from pathlib import Path
+
+
+_MINIMAL_MANIFEST = {
+    "agent_id": "00000000-0000-0000-0000-000000000042",
+    "role": "main_pm",
+    "team": "management",
+    "workspace_path": "/tmp/test",
+    "flow_tools": ["i_will_plan", "triage_all", "unblock", "complete", "i_am_idle"],
+    "do_tools": [],
+    "read_tools": [],
+    "write_tools": [],
+    "bash_allowed": False,
+    "subagent_allowed": False,
+    "subagent_model": None,
+    "env": {},
+}
+
+
+@pytest.fixture()
+def flow_module(
+    monkeypatch: pytest.MonkeyPatch, tmp_path: Path
+) -> types.ModuleType:
+    """Import flow_server with minimal env vars needed for constant inspection."""
+    manifest_path = tmp_path / "tool-manifest.json"
+    manifest_path.write_text(json.dumps(_MINIMAL_MANIFEST))
+
+    monkeypatch.setenv("ROBOCO_AGENT_ID", "00000000-0000-0000-0000-000000000042")
+    monkeypatch.setenv("ROBOCO_AGENT_ROLE", "main_pm")
+    monkeypatch.setenv("ROBOCO_ORCHESTRATOR_URL", "http://test-orchestrator:8000")
+    monkeypatch.setenv("ROBOCO_SDK_URL", "http://test-sdk:9000")
+    monkeypatch.setenv("ROBOCO_TOOL_MANIFEST_PATH", str(manifest_path))
+
+    import roboco.mcp.flow_server as srv
+
+    importlib.reload(srv)
+    return srv
+
+
+def test_circuit_kinds_include_incomplete_input(
+    flow_module: types.ModuleType,
+) -> None:
+    """incomplete_input is in the breaker's rejection-kind set."""
+    assert "incomplete_input" in flow_module._CIRCUIT_REJECTION_KINDS
+
+
+def test_circuit_kinds_include_tracing_gap(
+    flow_module: types.ModuleType,
+) -> None:
+    """Regression: tracing_gap stays in the set (the original kind)."""
+    assert "tracing_gap" in flow_module._CIRCUIT_REJECTION_KINDS