feat(api/v2): store user agent details in the session (#6711)

This change adds the ability to set and get user agent data, such as fingerprint, IP, request headers and a description to the session. All fields are optional.

Closes #6028

proto/zitadel/session/v2beta/session.proto

@@ -39,6 +39,7 @@ message Session {
       description: "\"custom key value list\"";
     }
   ];
+  UserAgent user_agent = 7;
 }
 
 message Factors {
@@ -131,3 +132,18 @@ message SearchQuery {
 message IDsQuery {
   repeated string ids = 1;
 }
+
+message UserAgent {
+  optional string fingerprint_id = 1;
+  optional string ip  = 2;
+  optional string description = 3;
+
+  // A header may have multiple values.
+  // In Go, headers are defined
+  // as map[string][]string, but protobuf
+  // doesn't allow this scheme.
+  message HeaderValues {
+    repeated string values = 1;
+  }
+  map<string,HeaderValues> header = 4;
+}

proto/zitadel/session/v2beta/session_service.proto

@@ -274,6 +274,7 @@ message CreateSessionRequest{
     }
   ];
   RequestChallenges challenges = 3;
+  UserAgent user_agent = 4;
 }
 
 message CreateSessionResponse{