Add IcebergData proto messages and regenerate SDKs

Add IcebergLocator, IcebergConfig, IcebergData protobuf messages to
logic.proto and extend Data oneof with iceberg_data variant. Regenerate
Julia, Python, and Go SDK bindings.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: vustef

proto/relationalai/lqp/v1/logic.proto

@@ -228,14 +228,14 @@ message Attribute {
 }
 
 //
-// Input data (base relations, CSVs)
+// Input data (base relations, CSVs, Iceberg)
 //
 message Data {
   oneof data_type {
     EDB edb = 1;
     BeTreeRelation betree_relation = 2;
     CSVData csv_data = 3;
-    // IcebergData iceberg_data = 4;
+    IcebergData iceberg_data = 4;
   }
 }
 
@@ -314,6 +314,26 @@ message CSVConfig {
   int64 partition_size_mb = 12;
 }
 
+message IcebergData {
+  IcebergLocator locator = 1;
+  IcebergConfig config = 2;
+  repeated GNFColumn columns = 3;
+  optional string to_snapshot = 4;
+}
+
+message IcebergLocator {
+  string table_name = 1;
+  repeated string namespace = 2;
+  string warehouse = 3;
+}
+
+message IcebergConfig {
+  string catalog_uri = 1;
+  optional string scope = 2;
+  map<string, string> properties = 3;
+  map<string, string> credentials = 4;
+}
+
 message GNFColumn {
   repeated string column_path = 1; // Column identifier path (was: string column_name)
   optional RelationId target_id = 2; // Target relation (now explicit optional)