chore: import upstream snapshot with attribution

conformance/agent-surface/classification.json

@@ -0,0 +1,46 @@
+{
+  "schema": 1,
+  "purpose": "Track minimized agent-surface repros without preserving report source context.",
+  "fixtures": [
+    {
+      "id": "interface-method-generic-binding",
+      "path": "conformance/agent-surface/fixtures/interface-method-generic-binding.0",
+      "classification": "intended-behavior",
+      "currentBehavior": "check-pass",
+      "followUp": "Keep interface method generic binders independent from interface type parameters.",
+      "runner": "assert-check-pass"
+    },
+    {
+      "id": "direct-generic-recursion",
+      "path": "conformance/agent-surface/fixtures/direct-generic-recursion.0",
+      "classification": "intended-behavior",
+      "currentBehavior": "check-pass-target-ready",
+      "followUp": "Keep self-recursive generic call targets present in the direct backend function table.",
+      "runner": "assert-target-ready"
+    },
+    {
+      "id": "direct-generic-specialization-name-collision",
+      "path": "conformance/agent-surface/fixtures/direct-generic-specialization-name-collision.0",
+      "classification": "unsupported-program-shape",
+      "currentBehavior": "check-pass-target-blocked-BLD004",
+      "followUp": "Keep direct generic specialization names from silently resolving to unrelated concrete functions.",
+      "runner": "assert-target-blocked"
+    },
+    {
+      "id": "stdlib-signature-parity",
+      "path": "scripts/compiler-metrics.mts",
+      "classification": "enforced-structure-guardrail",
+      "currentBehavior": "budget-pass-no-violations",
+      "followUp": "Keep compiler structure budgets enforced for file size, strcmp growth, large functions, and stdlib signature parity until one standard-library signature and capability source replaces duplicated metadata.",
+      "runner": "assert-budget-pass"
+    },
+    {
+      "id": "owned-drop-direct-backend-unsupported",
+      "path": "conformance/agent-surface/fixtures/owned-drop-direct-backend-unsupported.0",
+      "classification": "target-buildability-blocker",
+      "currentBehavior": "check-pass-target-blocked-BLD004",
+      "followUp": "Keep target-aware backend blockers before emission and keep backend diagnostics target-correct.",
+      "runner": "assert-diagnostic-code"
+    }
+  ]
+}