feat: implement Phase 23 - VC Manager

evolution/vc_manager.py

@@ -0,0 +1,55 @@
+"""Phase 23: Verifiable Credentials (VC) Manager.
+
+Issues and verifies W3C Verifiable Credentials and Presentations.
+"""
+
+import logging
+import json
+from typing import List, Dict, Any
+from agent.gemini_adapter import GeminiAdapter
+
+logger = logging.getLogger(__name__)
+
+class VCManager:
+    def __init__(self):
+        self.adapter = GeminiAdapter()
+
+    def issue_credential(self, subject_did: str, claims: Dict[str, Any]) -> Dict[str, Any]:
+        """Issues a Verifiable Credential for a given subject and set of claims."""
+        logger.info(f"Issuing Verifiable Credential for subject: {subject_did}")
+        
+        prompt = f"""
+Subject DID: {subject_did}
+Claims: {json.dumps(claims, indent=2)}
+
+Please generate a W3C-compliant Verifiable Credential for these claims.
+Include the proof (signature) metadata and the credential schema.
+Identify the 'Privacy-Preserving Safeguards' implemented in this credential.
+
+Format the output as JSON:
+{{
+  "credential": {{
+    "@context": [...],
+    "type": ["VerifiableCredential", "..."],
+    "issuer": "did:key:...",
+    "issuanceDate": "...",
+    "credentialSubject": {{
+      "id": "{subject_did}",
+      ...
+    }},
+    "proof": {{...}}
+  }},
+  "privacy_safeguards": [...],
+  "verification_directives": "..."
+}}
+"""
+        result = self.adapter.generate(
+            model="gemini-3.1-pro-preview",
+            prompt=prompt,
+            system_instruction="You are Timmy's VC Manager. Your goal is to ensure Timmy can issue and verify credentials with absolute cryptographic certainty.",
+            thinking=True,
+            response_mime_type="application/json"
+        )
+        
+        vc_data = json.loads(result["text"])
+        return vc_data