[Bug]: Fix: enforce required identity fields (name + email/phone)

src/IdentityToken.sol

@@ -76,6 +76,25 @@ contract IdentityToken is ERC721, IIdentityToken {
         return tokenId;
     }
 
+    /**
+     * @dev Adds validation to ensure required identity fields are present.
+     *      Name is mandatory and at least one contact method (email or phone)
+     *      must be provided.
+     */
+    function _validateRequiredFields(uint256 tokenId) internal view {
+        bytes memory name = attributes[tokenId][keccak256(abi.encodePacked("name"))];
+        bytes memory email = attributes[tokenId][keccak256(abi.encodePacked("email"))];
+        bytes memory phone = attributes[tokenId][keccak256(abi.encodePacked("phone"))];
+
+        // Name is mandatory
+        if (name.length == 0) revert Errors.MissingName();
+
+        // At least one contact method required
+        if (email.length == 0 && phone.length == 0) {
+            revert Errors.MissingContact();
+        }
+    }
+
     /**
      * @dev Sets a metadata attribute (e.g., name, social link) for an identity.
      */
@@ -85,6 +104,8 @@ contract IdentityToken is ERC721, IIdentityToken {
         bytes calldata value
     ) external onlyTokenOwner(tokenId) notCompromised(tokenId) {
         _setAttribute(tokenId, key, value);
+
+        _validateRequiredFields(tokenId);
     }
 
     /**

src/libraries/Errors.sol

@@ -16,4 +16,6 @@ library Errors {
     error AlreadyHasIdentity();
     error DuplicateEndorsement();
     error ArrayLengthMismatch();
+    error MissingName();
+    error MissingContact();
 }