fix release: actually, _this_ is going to be 25.6.1 ..

[oberstet]

Description

fix release: actually, this is going to be 25.6.1 ..

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Related Issue(s)

Closes #191

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Checklist

• I have referenced relevant issue numbers above
• I have performed a self-review of my code
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• My code follows the style guidelines of this project

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