Add version lookup in composer.json

[Jany-M]

Would be great if you could integrate a version lookup when editing composer.json (like what happens in package.json) or when using this extension.

[ikappas]

Anyone interested in picking this up for development?

[ikappas]

After some research I found these relevant commits for vscode built-in npm package version on hover

https://github.com/microsoft/vscode/blob/1.66.0/extensions/npm/src/features/jsonContributions.ts https://github.com/microsoft/vscode/blob/1.66.0/extensions/npm/src/features/packageJSONContribution.ts