Feature/qr code scaling

[Foxobot]

Prerequisites checklist

• I have read the contributing guidelines.

What is the purpose of this pull request? (put an "x" next to an item)

• Documentation update
• Bug fix
• New feature
• Other, please explain:

fixes issue #1547

What changes did you make? (Give an overview)

I added 3 new Config Parameters into print tree:

• qrPositionMode, options:
  - absolute: nothing changes, behaviour of qr-code size and offset as before
  - relative: new parameters qrRelativeSize and qrRelativeOffset are used to scale and place the qr code on print.
• qrRelativeSize: relative to print picture width
• qrRelativeOffset: relative to print picture width

Inserted relative scaling and positioning into src/Image.php. Only active when qrPositionMode=relative

Is there anything you'd like reviewers to focus on?

Maybe there is a more elegant way to have the two sets of parameters in the config page (for example not showing the absolute parameters when relative is selected?)

AI used to create this Pull Request?

AI was used to navigate through the project to find the files that need changes. AI was used to give an hint how the changes can be made minimal-invasive to the existing code.

[andi34]

npm run format
npm run composer:cgl

[reloxx13]

Addressed the review findings on this branch.

Fixed:

• Relative QR sizing/offset is now based on the final cropped print dimensions instead of the pre-crop source image.
• Theme export/import now includes print[qrPositionMode], print[qrRelativeSize], and print[qrRelativeOffset].
• Centered relative QR placement no longer passes half-pixel coordinates into imagecopy(), so the PHP 8.4 Implicit conversion from float to int loses precision deprecation path is gone.

Tests/validation added:

• Added PHPUnit coverage for crop-aware relative QR placement.
• Added a PHPUnit regression test that installs an E_DEPRECATED handler and exercises a centered relative QR placement case.
• Verified with ddev composer lint, ddev composer cgl, ddev composer phpstan, and ddev composer phpunit.

Intentional behavior choice:

• I did not preserve text rendering above the QR code. Per product clarification, QR readability is more important than overlapping text, so QR remains on top when both are enabled.

Latest commit on the PR branch: 5f0eb4bc (fix relative QR print placement).