US09-05: Automate Documentation Acceptance

tests/integration/test_user_manual.py

@@ -14,6 +14,8 @@ from __future__ import annotations
 import re
 from pathlib import Path
 
+import pytest
+
 REPO = Path(__file__).resolve().parents[2]
 DOCS = REPO / "docs"
 STAGES = DOCS / "stages"
@@ -55,6 +57,9 @@ STAGE_PAGES = (
     "diagnostics",
 )
 
+# Every check here belongs to the documentation gate (US09-05).
+pytestmark = pytest.mark.phase_i
+
 
 def emitted_codes() -> set[str]:
     found: set[str] = set()