Fix websocket server proto definitions to include top-level enums

The websocket server's "protos" request handler was using
descriptor->DebugString() which only outputs message definitions,
causing top-level enums (like PixelFormatType) to be omitted from
the generated proto definitions sent to clients.

This caused protobuf.js clients to fail parsing the definitions
because messages referenced enum types that were never defined.

Changes:
- Extract and include all top-level enums from each proto file
- Use fileDescriptor->enum_type_count() to iterate enums
- Add deduplication sets for both files and enums
- Keep using descriptor->DebugString() for messages to avoid
  including import statements that would break single-file parsing

The generated proto now includes all necessary enum definitions
while remaining compatible with protobuf.js single-file parsing.

Fixes missing PixelFormatType, SphericalCoordinatesType, and other
top-level enums in the websocket proto definitions.

Signed-off-by: cmeng <[email protected]>

Author: cmeng-gao

src/systems/websocket_server/WebsocketServer.cc

@@ -715,11 +715,15 @@ void WebsocketServer::OnMessage(int _socketId, const std::string _msg)
     gzdbg << "Protos request received\n";
 
     std::string allProtos = "syntax = \"proto3\";\n";
-    allProtos += "package gz.msgs;\n";
+    allProtos += "package gz.msgs;\n\n";
 
     std::vector<std::string> types;
     gz::msgs::Factory::Types(types);
 
+    // Track processed files and enums to avoid duplicates
+    std::set<const google::protobuf::FileDescriptor*> processedFiles;
+    std::set<const google::protobuf::EnumDescriptor*> processedEnums;
+
     // Get all the messages, and build a single proto to send to the client.
     for (auto const &type : types)
     {
@@ -739,7 +743,28 @@ void WebsocketServer::OnMessage(int _socketId, const std::string _msg)
           continue;
 
         if (descriptor)
+        {
+          auto fileDescriptor = descriptor->file();
+
+          // Only process each file once to extract top-level enums
+          if (processedFiles.insert(fileDescriptor).second)
+          {
+            // Extract all top-level enums from this file
+            for (int i = 0; i < fileDescriptor->enum_type_count(); ++i)
+            {
+              auto enumDescriptor = fileDescriptor->enum_type(i);
+              if (processedEnums.insert(enumDescriptor).second)
+              {
+                allProtos += enumDescriptor->DebugString();
+                allProtos += "\n";
+              }
+            }
+          }
+
+          // Add the message definition (without file-level import statements)
           allProtos += descriptor->DebugString();
+          allProtos += "\n";
+        }
         else
         {
           gzerr << "Failed to get the descriptor for message["