fix(node): version ref_certificates for forward compat (#26 split 3/4)

README.md

@@ -311,6 +311,7 @@ metadata        local disk / optional S3
 | DID | A user, agent, or node identity derived from an Ed25519 public key. |
 | HTTP Signature | RFC 9421 signature proving control of the DID key for write requests. |
 | Ref certificate | Signed record of a ref update. Useful for audit and replication. |
+| Ref certificate versioning | The wire format is versioned; new certificates are currently issued as v1. `gl cert show <repo> <id> --verify` requires `--expect-node <did>`, and the queried node's self-reported DID is **not** accepted as a trust anchor. v2 is reserved for a future payload shape that carries the version inside the signed bytes; this client refuses to verify v2+ rather than guessing. |
 | UCAN | Delegation token for future capability-based workflows. |
 | Peer announce | Node-to-node HTTP announcement of DID + public URL. |
 | Gossipsub | libp2p topic for ref-update events. |

crates/gitlawb-node/src/api/certs.rs

@@ -52,6 +52,7 @@ pub async fn list_certs(
                 "node_did":   c.node_did,
                 "signature":  c.signature,
                 "issued_at":  c.issued_at,
+                "version":    c.version,
             })
         })
         .collect();
@@ -92,5 +93,6 @@ pub async fn get_cert(
         "node_did":   cert.node_did,
         "signature":  cert.signature,
         "issued_at":  cert.issued_at,
+        "version":    cert.version,
     })))
 }

crates/gitlawb-node/src/api/events.rs

@@ -437,6 +437,7 @@ mod ref_updates_feed_tests {
             node_did: "did:key:z6MkNode".into(),
             signature: "sig".into(),
             issued_at: Utc::now().to_rfc3339(),
+            version: 1,
         }
     }