Add API for setting custom window dimensions

[kephale]

Summary

This PR addresses issue #616 by adding an API to set custom width/height for the sciview window. This functionality is essential for VR headsets that require specific resolutions.

Changes

New API Methods

• setWindowSize(width: Int, height: Int): Boolean - Sets custom window dimensions
• getWindowSize(): Pair<Int, Int> - Returns current window dimensions
• create(width: Int, height: Int): SciView - Factory method to create SciView with initial dimensions

Implementation Details

• Window dimensions are validated to ensure they are positive
• The renderer is properly resized when dimensions change
• Camera aspect ratio is updated to match new dimensions
• Proper error handling with logging

Additional Files

• CustomWindowSizeDemo.kt - Demo showing how to use the API with visual markers
• WindowSizingTest.kt - Unit tests for the new functionality
• README.md - Updated with API documentation and examples

Testing

The implementation has been tested with:

• Valid window dimensions (various resolutions)
• Invalid dimensions (negative/zero values)
• Camera aspect ratio updates
• Renderer resizing

Use Cases

This API is particularly useful for:

• VR headset integration (e.g., Oculus Quest 2 at 2880x1700)
• Multi-monitor setups
• Creating screenshots/recordings at specific resolutions
• Kiosk or presentation modes

Example Usage

// Create with custom dimensions
val sciview = SciView.create(1920, 1080)

// Or resize existing instance
sciview.setWindowSize(2880, 1700)

// Query current size
val (width, height) = sciview.getWindowSize()

Closes #616

[smlpt]

Thanks a lot! @kephale
There are a few things that don't work out on my side though.
First, MenuWeights.DEMO_BASIC_CUSTOM_WINDOW in CustomWindowSizeDemo doesn't exist.
Then, Sciview.create() exists twice and throws an overload error (did you happen to vibe code this or was it just very late? :)
And lastly, updating to POM 40.0.0 creates this error for me:

Could not find net.imagej:ij1-patcher:1.2.8.
     Searched in the following locations:
       - https://maven.scijava.org/content/groups/public/net/imagej/ij1-patcher/1.2.8/ij1-patcher-1.2.8.pom
     Required by:
         project :sciview > org.scijava:pom-scijava:40.0.0 > sc.fiji:fiji-lib:2.1.3

Same requirement for net.imagej:imagej-legacy:2.0.0

Reverting to 37 fixes it. Could be that it conflicts with the other repositories (scenery and manvr3d) next to sciview.

[smlpt]

In #616 you wrote that the CI was fixed by updating to org.scijava:scijava-common:2.99.0 but re-running the CI still fails.

[kephale]

@smlpt yeah, this wasn't really for review. I don't have a lot of bandwidth for this now (sciview isn't part of my day-to-day work anymore) so I just wanted to see what could be autocompleted.

I'm happy to close this and review a PR if you want to submit. Otherwise I'm not sure when I'll be able to revisit this.

[smlpt]

@kephale I see. You could have told me that you don't have time to work on sciview right now, I would have understood.
Either way, I fixed the most prominent bugs I think.
There's still a (general) issue, likely the same as #553, that causes the actual window size to be bigger than it should be, at least on Windows with window scaling >100%. I'm on a 2560p laptop here, and setting the sciview window to 1920x1080p causes it to be larger than the screen, which is plausible given my 150% window scaling.
If you don't have time to investigate this, maybe @skalarproduktraum has?

On a side note, Sciview.setWindowsSize is calling VulkanRenderer.reshape, which is an empty method. Not sure what to make of that.

[kephale]

@smlpt Sorry, circumstances changed. I expected to be available again by now.

I can check/merge if you'd like. I'm not going to have time to do any proper testing for the next ~month.

[smlpt]

@kephale thanks! I'm just trying to figure out the remaining issue with inconsistent renderer sizes after a window resizing event now, then we can merge this. @skalarproduktraum is aware of the issue and we'll look into it today or next week.