graphify: index ourdigital-okf skill into knowledge graph

OKF-scoped --update of custom-skills/97-ourdigital-okf (7 code + 19 docs):
+131 nodes (62 AST + 75 semantic), +207 edges, 8 OKF communities, 6 hyperedges
capturing the produce/validate/visualize design and zero-dep utility trio.
Prior graph was code-only; the OKF skill is now queryable. ~172k extraction tokens.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

graphify-out/cost.json

@@ -0,0 +1,13 @@
+{
+  "runs": [
+    {
+      "date": "2026-06-17",
+      "input_tokens": 171924,
+      "output_tokens": 0,
+      "files": 26,
+      "note": "OKF-scoped --update"
+    }
+  ],
+  "total_input_tokens": 171924,
+  "total_output_tokens": 0
+}