Extractor: drawio → absolute_layout YAML scaffold (107/132 cached)

Closes the procedural hole that kept making Codex sessions fall back
to ``examples/`` for YAML scaffolding even after the SKILL forbade it.

The lookup tool returns a canonical Oracle ``.drawio`` as the geometry
source, but the agent had no YAML version of that geometry to copy —
the .drawio is XML with stencil-encoded icons. Without a scaffold,
agents reverse-engineered or fell back to ``examples/`` (which is
forbidden but happened anyway because the alternative was painful).

New tool ``tools/archcenter_drawio_to_template.py`` extracts:
  • canvas dimensions
  • containers (region / vcn / ad / subnet) classified by stroke /
    fill style markers
  • service bounding boxes with ``type: TODO_identify`` (the icon
    type is encoded in stencil bytes — agent fills it from the
    renderer's TYPE_TO_ICON aliases when authoring the spec)
  • edge waypoints (source, target, points)

Output lands at ``kb/diagram/assets/archcenter-refs/<slug>/_template.yaml``
next to the .drawio. Lookup now surfaces it as
``cached: yaml=<path>`` so the agent has a one-step "copy this YAML
and adapt" path.

Ran across all 132 cached folders: 107 templates emitted, 24 had no
.drawio (zip didn't ship one), 1 already cached.

Other persistent guardrails added in this commit:

- SKILL.md option 2 step 3: explicit reminder that valid ``type:``
  values come from ``TYPE_TO_ICON`` / ``ICON_TYPE_ALIASES`` in the
  renderer source plus the icon-index JSON files. Do NOT grep
  ``examples/`` for ``type:`` — that's where the previous Codex
  session was looking, against the rule.

- ``make archcenter-templates-refresh`` Makefile target.

- The lookup index now also indexes ``_template.yaml`` per slug.

- Auto-extracted templates committed under
  ``kb/diagram/assets/archcenter-refs/*/_template.yaml`` so a fresh
  clone has them on first lookup (no extraction step needed).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tools/archcenter_pattern_lookup.py

@@ -248,6 +248,12 @@ def _build_cache_dir_index() -> dict[str, dict[str, str]]:
             for path in sub.rglob(f"*.{ext}"):
                 bucket[ext] = str(path.relative_to(PROJECT_ROOT))
                 break  # only the first hit per ext is enough
+        # Surface the auto-extracted absolute_layout template if present.
+        # Agents read this YAML as the spec scaffold (Oracle's canonical
+        # geometry) — generated by tools/archcenter_drawio_to_template.py.
+        template = sub / "_template.yaml"
+        if template.is_file():
+            bucket["yaml"] = str(template.relative_to(PROJECT_ROOT))
         if bucket:
             index[sub.name] = bucket
 
@@ -265,9 +271,16 @@ def _build_cache_dir_index() -> dict[str, dict[str, str]]:
 
 
 def _cached_assets(entry: dict) -> dict:
-    """Find .drawio / .png / .svg if a matching folder is cached locally.
-    Served from the one-shot in-memory index built by
-    ``_build_cache_dir_index``."""
+    """Find .drawio / .png / .svg / _template.yaml if a matching folder
+    is cached locally. Served from the one-shot in-memory index built
+    by ``_build_cache_dir_index``.
+
+    The ``yaml`` key (when present) points to ``_template.yaml`` — the
+    auto-extracted absolute_layout scaffold from
+    ``tools/archcenter_drawio_to_template.py``. Agents should copy this
+    YAML as the starting point for a new spec instead of falling back
+    to ``examples/`` (which is forbidden as a geometry source).
+    """
     cache_index = _build_cache_dir_index()
     if not cache_index:
         return {}