[Enhancement] Messaging toast refactor

[alvroble]

Description

This PR is a toast refactor as @easyuxd's UX guidelines in https://github.com/SeedSigner/seedsigner/issues/606. Changes are the following:

• Add toast messaging categories
• General sizing refactor
• Unbind icon color from text color
• Dynamically adjust toast height
• ToastOverlay is now available to use with no icon
• New DIRE_WARNING_COLOR=#FF453A and ERROR_COLOR=#AD2013

Screenshots for some examples:

Dynamic height adjustment:

To do:

• [ ] New "info" icon. I can get the seedsigner-icons.otf from #586.
• [ ] More tests around the delay increase (0.2s) in the lock mechanism to ensure that a button press won’t interfere with a toast displayed immediately afterward.

This pull request is categorized as a:

• [x] New feature
• [ ] Bug fix
• [x] Code refactor
• [ ] Documentation
• [ ] Other

Checklist

• [ ] I’ve run pytest and made sure all unit tests pass before sumbitting the PR

If you modified or added functionality/workflow, did you add new unit tests?

• [ ] No, I’m a fool
• [x] Yes
• [ ] N/A

I have tested this PR on the following platforms/os:

• [x] Raspberry Pi OS Manual Build
• [ ] SeedSigner OS on a Pi0/Pi0W board
• [ ] Other

Note: Keep your changes limited in scope; if you uncover other issues or improvements along the way, ideally submit those as a separate PR. The more complicated the PR the harder to review, test, and merge.

[easyuxd]

Beautiful work, @alvroble -- thanks for doing this. The toast categories look great so far, and the dynamic height adjustment is clean!