Moved fomantic dropdown css to custom module, tested on the dropdown
devtest page, it renders exactly the same as before while using roughly
50% less CSS. The clean up was very conservative, likely more can be
done in the future.
Also, this fixes a bug present on main branch where dropdown border has
incorrect color on hover.
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Signed-off-by: silverwind <[email protected]>
Co-authored-by: Claude Opus 4.5 <[email protected]>
