feat(#62): IMP-46 cache fingerprint forwarding u1~u4 (router kwarg + step12 forward + 8 scenarios)

src/phase_z2_ai_fallback/step12.py

@@ -200,6 +200,7 @@ def gather_step12_ai_repair_proposals(
                 figma_partial_json=figma_partial_json,
                 internal_region=internal_region,
                 mdx_text=mdx_text,
+                fingerprints=fingerprints,
             )
         except Exception as exc:  # noqa: BLE001 — record + continue, no AI re-raise
             record["ai_called"] = True