feature: add temperature graph

[ClementTsang]

Description

A description of the change, what it does, and why it was made. If relevant (e.g. UI changes), please also provide screenshots/recordings:

WIP

Quick-and-dirty implementation for now, will clean this up with other widgets later (maybe after adding a disk graph widget).

Issue

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Closes: #1366

Testing

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• Windows
• macOS (specify version below)
• Linux (specify distro below)
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Checklist

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• If this PR adds or changes a dependency, please justify this in the description
• If this is a code change, areas your change affects have been linted using (cargo fmt)
• If this is a code change, your changes pass cargo clippy --all -- -D warnings
• If this is a code change, new tests were added if relevant
• If this is a code change, your changes pass cargo test
• The change has been tested to work (see above) and doesn't appear to break other things
• Documentation has been updated if needed (README.md, help menu, docs, configs, etc.)
• There are no merge conflicts
• You have reviewed your changes first
• The pull request passes the provided CI pipeline

Other

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