Added local caching mechanism for list of polkadot-sdk versions to fasten fetch time

[0xsouravm]

This PR introduces a --cache flag to locally store the list of polkadot-sdk versions to exponentially fasten their fetch time compared to the GitHub API or CLI. A --update-cache flag is also added to just update the local cache by freshly fetching the available versions from GitHub.

Key Features:

1. Cache the versions list to fetch the versions lightning-fast
2. Update the local cache by freshly fetching versions list from GitHub

[ggwpez]

Please not. This tool is very simple. We should keep it simple and only exactly as complicated as necessary.

I dont see any reason to add caching. Projects will use this maybe once per month - most. There is no way we need a cache in this. It this tool was often used, or somehow time critical then i would say yes, but not for this.

This tool has to stay very simple, since it only shows a miss design in how we currently handle releases. It is meant as intermediate solution and nothing that we should try to massively extend. There is no gain from this.

If you want to make a CLI faster, i would suggest https://github.com/paritytech/try-runtime-cli, it runs in CI on every pull request and is currently using CI cached files. It takes about 15 min or more to create a snapshot, but is also difficult to optimize. Anyway, any effort spent here should rather go to a more value bearing project.

[0xsouravm]

Please not. This tool is very simple. We should keep it simple and only exactly as complicated as necessary.

I dont see any reason to add caching. Projects will use this maybe once per month - most. There is no way we need a cache in this. It this tool was often used, or somehow time critical then i would say yes, but not for this.

This tool has to stay very simple, since it only shows a miss design in how we currently handle releases. It is meant as intermediate solution and nothing that we should try to massively extend. There is no gain from this.

Oh alright got it. Sorry I thought it would be helpful. Thanks!

[0xsouravm]

If you want to make a CLI faster, i would suggest https://github.com/paritytech/try-runtime-cli, it runs in CI on every pull request and is currently using CI cached files. It takes about 15 min or more to create a snapshot, but is also difficult to optimize. Anyway, any effort spent here should rather go to a more value bearing project.

Sure I will give it a look! Thank you so much!