Fix a colour token in light mode on the SendButton.

[pixlwave]

Use light/icon/on-solid-primary instead of dark/icon/primary in light mode. This also removes the need to override the colour scheme now seeing as the gradient isn't using reactive colours either.

It's hard to see but there is a difference to the light mode compared to #130:

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.65%. Comparing base (78e1290) to head (cc26ed8).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #131   +/-   ##
=======================================
  Coverage   96.65%   96.65%           
=======================================
  Files          22       22           
  Lines        1374     1374           
=======================================
  Hits         1328     1328           
  Misses         46       46           

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[stefanceriu]

👍