feat: add in-keyboard clipboard history manager

[Roniscend]

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

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Description

Introduces a new clipboard key that opens a persistent, Room-backed history panel with copy/paste suggestions, pinning, deleting, and dark-mode support.
Fixes: #459

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[github-actions]

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[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 :)

• Tests for changes have been written and the unit test, linting and formatting 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)