Document VM release process

[marceltaeumel]

Here is a draft.

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How to make a new RC of the OSVM:

1. Tag specific commit with its UTC timestamp, e.g., 202205110711 for May 11, 2022 at 7:11
2. Run all "Build for*" workflows manually for that tag
3. Verify that a pre-release was created for that tag, containing all build artifacts
4. Write an email to the vm-dev mailing list

How to make a new release of the OSVM:

1. Do a new RC (see above)
2. Edit that GitHub pre-release to be an actual release
3. Change the description to have some release notes on the changes
4. Write an "[ANN] ..." email to vm-dev mailing list

How to make use of OSVM-RC in squeak-app bundles:

1. Maybe do a new RC (see above)
2. In any branch's bundle.yml, set VM_RC_TAG in prepare-bundles job to the RC tag
3. Write an email to the squeak-dev mailing list

How to make use of a new OSVM release in squeak-app bundles:

1. Maybe make a new VM release (see above)
2. Update the files in http://files.squeak.org/base/ for the Squeak versions of your choice
3. :warning: Watch out for minor differences between OSVM packaging and what vm-*.zip expects. For example, Linux has an extra indirection that needs to be removed. And those macOS .dmg packages have to be converted to .zip for squeak-app.
4. Write an email to the squeak-dev mailing list

[LinqLover]

How to make use of a new OSVM release in squeak-app bundles:

1. Maybe make a new VM release (see above)
2. Update the files in http://files.squeak.org/base/ for the Squeak versions of your choice
3. ⚠️ Watch out for minor differences between OSVM packaging and what vm-*.zip expects. For example, Linux has an extra indirection that needs to be removed. And those macOS .dmg packages have to be converted to .zip for squeak-app.
4. Write an email to the squeak-dev mailing list

5. Bump SystemVersion>>#recommendedVMBuildNumber in Squeak-Trunk (or maybe also in older Squeak versions >= Squeak 6.1)