feat(ui): dark theme

[rpelczar]

Description

Closes #6061

Checklist

Eligibility

• Linked to an existing issue with no blocking labels (kind/proposal, needs discussion, needs research, maintainer only, area/security, size/large, size/x-large, size/xx-large).
• Changes documentation only.
• Changes ten lines or fewer.

Quality

• Adds or updates corresponding tests.
• Adds or updates corresponding documentation.

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• By a human without AI assistance.
• By a human with AI assistance. A human has reviewed every line prior to opening the PR.
• By an AI with human supervision. A human has reviewed every line prior to opening the PR.
• Entirely by an AI. No human has reviewed this prior to opening the PR.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 31.10%. Comparing base (bc16c85) to head (4600cc3).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6838   +/-   ##
=======================================
  Coverage   31.10%   31.10%           
=======================================
  Files         832      832           
  Lines       81199    81199           
=======================================
  Hits        25258    25258           
  Misses      54470    54470           
  Partials     1471     1471           

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[jmalisz-akuity]

Overall looks solid, with 2 minor issues.

To keep the same convention those question marks probably should use dark:text-neutral-500:

Not sure exactly where this color and bg comes from, but IMO the contrast is too low here: