feat: complete pre-ai local completion v3

central/app/ai/cache_policy.py

@@ -0,0 +1,30 @@
+"""Pure cache and dataset-freshness policies for offline and real evaluations."""
+
+import hashlib
+import json
+
+
+VALID, NEEDS_REVALIDATION, CONFLICT = "VALID", "NEEDS_REVALIDATION", "CONFLICT"
+
+
+def cache_key(input_fingerprint, candidate_set_hash, model, prompt_version, dataset_versions):
+    """Return a stable key covering every input that can change an answer."""
+    payload = {
+        "input_fingerprint": str(input_fingerprint),
+        "candidate_set_hash": str(candidate_set_hash),
+        "model": str(model),
+        "prompt_version": str(prompt_version),
+        "dataset_versions": dict(sorted((dataset_versions or {}).items())),
+    }
+    return hashlib.sha256(json.dumps(payload, sort_keys=True, separators=(",", ":")).encode()).hexdigest()
+
+
+def classify_knowledge_freshness(record_versions, active_versions):
+    """Classify versioned knowledge without deleting or rewriting history."""
+    recorded = dict(record_versions or {})
+    active = dict(active_versions or {})
+    if any(key in recorded and key in active and recorded[key] != active[key] for key in recorded):
+        return CONFLICT
+    if recorded != active:
+        return NEEDS_REVALIDATION
+    return VALID