ui: buttons bitcoinview

[reez]

Description

iOS 26 related.

Move buttons to bottom.

Not sure exactly what icons/text to use or not yet (what I have is pretty bare at the moment), but that's not the main idea of this PR and can be updated later.

Notes to the reviewers

Changelog notice

Checklists

All Submissions:

• I've signed all my commits
• I have formatted my code with swift-format per .swift-format file

New Features:

• I've added tests for the new feature
• I've added docs for the new feature

Bugfixes:

• This pull request breaks the existing API
• I've added tests to reproduce the issue which are now passing
• I'm linking the issue being fixed by this PR