Add support for Celsius and Hertz units in metrics handling

[metalmatze]

Updated the utility functions and Y-axis unit mapping to handle Celsius and Hertz.

[alwaysmeticulous]

✅ Meticulous spotted 0 visual differences across 304 screens tested: view results.

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_{Expected differences? Click here. Last updated for commit 737f4b4. This comment will update as new commits are pushed.}