Add architecture to pre-seeded page_ids in lint_docs.py

architecture.md is gitignored (generated at build time), so the
linter glob never finds its anchor. Pre-seed it like the other
generated pages to prevent CI failure.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: sbryngelson

toolchain/mfc/lint_docs.py

@@ -371,7 +371,7 @@ def check_page_refs(repo_root: Path) -> list[str]:
 
     # Collect all @page identifiers (IDs may contain hyphens)
     # Include Doxygen built-ins and auto-generated pages (created by ./mfc.sh generate)
-    page_ids = {"citelist", "parameters", "case_constraints", "physics_constraints", "examples", "cli-reference"}
+    page_ids = {"citelist", "parameters", "case_constraints", "physics_constraints", "examples", "cli-reference", "architecture"}
     for md_file in doc_dir.glob("*.md"):
         text = md_file.read_text(encoding="utf-8")
         m = re.search(r"^\s*@page\s+([\w-]+)", text, flags=re.MULTILINE)