chore: clearer getting started output

[TomCools]

Description of the change

Our quickstarts were a mix between the "getting started" output and actual "use cases". This resolves that discrepancy.
Also moved some of the folder structure to better reflect "use cases" vs "getting started"

Checklist

Development

• The changes have been covered with tests, if necessary.
• You have a green build, with the exception of the flaky tests.
• UI and JS files are fully tested, the user interface works for all modules affected by your changes (e.g., solve and analyze buttons).
• The network calls work for all modules affected by your changes (e.g., solving a problem).
• The console messages are validated for all modules affected by your changes.

Code Review

• This pull request includes an explanatory title and description.
• The GitHub issue is linked.
• At least one other engineer has approved the changes.
• After PR is merged, inform the reporter.

[TomCools]

Build still failing, i think mainly due to changes on how the structure was setup (changes to the .github folder)

[TomCools]

Contra PR: TimefoldAI/timefold-solver#2459

[Copilot]

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[triceo]

Skimmed this. CI broken and cannot be fixed, because this is a large rfactor that first needs to be merged.