docs: update outdated script creation instructions

[dzied-baradzied]

Fixes #149. Updates the JBang Tool Window, README, and documentation to correctly state that JBang scripts are created via the Project View context menu.

[dzied-baradzied]

@maxandersen I ran into the same error you reported earlier: gradle/actions#631

1. Have you found any workaround? Maybe updating gradle/wrapper-validation-action to the latest version, as suggested in that issue, could help?

2. Am I right that this is a flaky error that can usually be fixed by restarting the job? If so, could you try restarting it, or let me know if there’s anything I can do to help?

This issue itself is minor and not urgent. However, I'm wating also for a review of another more urgent PR #148 It fixes critial issue. In my environment _JAVA_OPTIONS has a default value that I can’t easily unset and it crashes plugin. So, this is not the latest build that I need to pass :)