Add shadow to popup for better visual distinction above keyboard

[Femimat]

Contributor checklist

• This pull request is on a separate branch and not the main branch
• I have tested my code with the ./gradlew lintKotlin detekt test command as directed in the testing section of the contributing guide

---

Description

This PR adds a subtle grey shadow (#3F3F46) to the popup view that appears when users long-press keys with alternate characters (e.g., accented letters).
The shadow visually separates the popup from the keyboard, making it clearer that the view is layered above.
This update ensures consistent appearance across both light and dark themes.

Changes Made

Updated minikeyboard_background.xml to include shadow properties.
Adjusted layout styling in keyboard_popup_keyboard.xml.

Related issue

• Add shadow to alternate keys view #491

[github-actions]

Thank you for the pull request! ❤️

The Scribe-Android team will do our best to address your contribution as soon as we can. If you're not already a member of our public Matrix community, please consider joining! We'd suggest that you use the Element client as well as Element X for a mobile app, and definitely join the General and Android rooms once you're in. Also consider attending our bi-weekly Saturday dev syncs. It'd be great to meet you 😊

[github-actions]

Maintainer Checklist

The following is a checklist for maintainers to make sure this process goes as well as possible. Feel free to address the points below yourself in further commits if you realize that actions are needed :)

• The linting, formatting and testing workflows within the PR checks do not indicate new errors in the files changed

  • Tests may need to be reran as they're at times not deterministic

• The CHANGELOG has been updated with a description of the changes for the upcoming release and the corresponding issue (if necessary)

[andrewtavis]

Hey @Femimat 👋 I'm realizing that I might have been confused by the plans for this. Would we be able to add a small shadow to the views that's similar to what's under the keys? The background color for the alternate keys view should be the same as they keyboard background color. It'd be good if we had a shadow under it so it's clear that it's above they keyboard interface :)

[Femimat]

Hi @andrewtavis, I understand better now. I’ll go over it and see how I can implement the design.

[andrewtavis]

Sounds good, @Femimat! Looking forward to the update 😊

[Femimat]

Hey @andrewtavis! I’ve updated the PR — please have a look when you get a chance.

[DeleMike]

Hi @Femimat!

Thanks for the input!

---

Please can you avoid hardcoded colors - please reference a named color resource (e.g. @color/popup_shadow_color) for theme consistency.

• The popup looks a bit flat — maybe we can consider adding creating a more natural “shadowed” effect.

Nice work!

[Femimat]

Hi @DeleMike!
I’ll go over it and see how I can implement the design. thanks for the feedback.

[DeleMike]

Thanks so much! And I'm looking forward to it :)