feat: show Metals' release notes if server version is updated

[kpodsiad]

Motivation

Currently Metals updates are completely silent and I suspect that most of the users doesn't even know that update just happened. Not everyone has twitter account or is checking Metals' blog on regular basis and this kind of people (I suspect that most of the beginners?) can omit all of those juicy new features which are shipped with the new release.

It is a goal of this PR to provide some mechanism to inform user about latest changes.

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Other solutions

Currently, as far as I know, there is no mechanism for showing extension updates in vscode - see microsoft/vscode#102139. There are some ways to do it, for example I found https://github.com/alefragnani/vscode-whats-new but it seems like its use case is a bit different than what this PR needs (metals-vscode doesn't have any useful changes on its own).

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Goals

Show some indicator that update happened, maybe show embedded release notes in the webview panel?

No matter what indicator will be chosen it mechanism should:

• not show too often. Ideally only once, after first vscode window start with updated Metals extension
• not show when running metals e.g. on gitpod or other containers which install extension every time
• be able to be disabled in options

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Current state

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[tgodzik]

Great idea! 🎉 It would be similar to the VS Code updates that show up, which are really nice to check out. The main difficulty will be to make sure that we don't show it too often.

[kpodsiad]

I think PR is ready for review & testing.
Tests:

• MacOS - done by me
• Linux
• Windows (not sure how it'll work with wsl)
• remote containers (gitpod, codespaces) - I read that they start from scratch every time, better to not show release notes at all than show them every time
• synchronization between editors on local computer - release notes are showed only in first vscode instance, subsequent windows don't get them
• synchronization between devices - not necessary but nice to have & should work

[tanishiking]

@kpodsiad Thanks for kicking off, this is a great idea!

I remember GitLens extension shows a welcome/what's the new view if there're updates, so I checked how it is implemented.

• Sync the previous extension version using globalState.
• compare previous and current ones, if it's downgrade don't show what's new
• Otherwise, run ShowWelcomePage command to open a welcome.html that has a link to release notes
  • But it would be nicer if we can show the release notes directly, instead of showing the same welcome page every time we update the plugin.

Maybe we can store the server version in globalState and compare it with the previous ones. Nevermind! you already do this!

[tgodzik]

Current state

Could we improve the spacing maybe somehow? The text seems kind of squashed.

[kpodsiad]

@tgodzik I've increased margin for headers, it should be better now.

[tanishiking]

The change looks good to me! Let me playing around this change a bit :)

[kpodsiad]

I think author part needs some overhaul. Maybe simple prefix like Authored by: <author name with link to twitter (current content)>. What do you think?

[Arthurm1]

Is there a command to bring up the release notes? Maybe add show release notes in Help and Feedback?

[kpodsiad]

Is there a command to bring up the release notes? Maybe add show release notes in Help and Feedback?

Great idea @Arthurm1. I can both command and button in 'Help and Feedback'.

[kpodsiad]

I've added a command Metals: show release notes which will allow to open webview with current release notes.

[tgodzik]

Looks good! Let's just rebase on the main branch

[kpodsiad]

I'm merging, pre-release it's time to do your job :D

[tgodzik]

I reverted the PR in #1019 since it seems to have broke Metals at all.