Improve Documentation for ResizeImage Dimensions and Usage

[RamonFarizel]

This pull request enhances the documentation for the ResizeImage widget to provide clearer guidance on the use of the width and height parameters.

Fixes #136508

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• I followed the breaking change policy and added Data Driven Fixes where supported.
• All existing and new tests are passing.

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[nate-thegrate]

Thanks for the contribution!

I sort of crammed a bunch of feedback into this tiny addition, so take a look when you have a chance :)

[nate-thegrate]

LGTM (with optional whitespace nit)

Thanks for making the improvement here!

[RamonFarizel]

Thank you all for your support! It was nice to learn a bit more about all those details.

[goderbauer]

LGTM

[hwh97]

@RamonFarizel @nate-thegrate Hey, Can someone confirm whether the width parameter in ResizeImage refers to logical pixels instead of physical pixels? The original issue seems to describe it differently. Any clarification would be appreciated!

[nate-thegrate]

Thank you @hwh97, this is a really good question.

If you set width: 200, the image will be 200 physical pixels wide and will also size itself to a width of 200 logical pixels if unconstrained.

This means that if the image is constrained, the width parameter will only change the width with regards to image resolution.

I apologize for the confusion—originally my feedback on this PR was focused on syntax/grammar/style guidelines and I neglected to double-check that it matched the behavior. I'll go ahead and re-open #136508.