Mark/1281 Check if the frontend version is compatible

[markccchiang]

Description

• What is implemented or fixed? Mention the linked issue(s), if any. Fixes #1281.

• How does this PR solve the issue? Give a brief summary. The frontend sends its version info, e.q., 4.0.0, in the RegisterViewer message to the backend when connected. The backend then checks if the frontend version is compatible with it, plus the ICD version. If not, the backend sends success == false and an error message in the RegisterViewerAck to the frontend.

• Are there any companion PRs (frontend, protobuf)? Both companions frontend PR and protobuf PR are needed.

• Is there anything else that testers should know (e.g. exactly how to reproduce the issue)? When connected to the frontend, if the frontend version is not compatible with the backend. Then the frontend will receive success == false and an error message in the RegisterViewerAck from the backend. The frontend could show the error message on the panel to remind the user and disconnect with the backend.

Checklist

• [x] changelog updated ~/ no changelog update needed~
• [ ] e2e test passing / corresponding fix added / new e2e test created
• [x] protobuf updated to the latest dev commit ~/ no protobuf update needed~
• [ ] added reviewers and assignee
• [ ] added ZenHub estimate, milestone, and release

[github-actions[bot]]

Package	Line Rate	Health
src.Cache	66%	➖
src.DataStream	52%	➖
src.FileList	67%	➖
src.Frame	50%	➖
src.HttpServer	42%	➖
src.ImageData	28%	❌
src.ImageFitter	83%	✔
src.ImageGenerators	43%	➖
src.ImageStats	76%	✔
src.Logger	44%	➖
src.Main	54%	➖
src.Region	18%	❌
src.Session	29%	❌
src.Table	52%	➖
src.ThreadingManager	87%	✔
src.Timer	85%	✔
src.Util	49%	➖
Summary	38% (7090 / 18713)	❌

[confluence]

I am closing this because of the decision to solve this issue with a different approach to the ICD version. We will still need changes in the backend to support the new approach (to use a single location in the protobuf repo to store the ICD version, and possibly also to use a flag to set the strictness level for the ICD comparison), but this should be done in new PRs.