Fix dark mode search text contrast

[Ady0333]

Summary

This PR fixes a low-contrast issue in the search dropdown when using dark mode. The block labels inside the autocomplete list were rendered in dark gray text on a dark background, making them difficult to read.

What was happening

The search dropdown renders block labels inside tags. The jQuery UI base theme applies:

.ui-widget-content a { color: #333333; }

This overrides the inherited white text color in dark mode, resulting in dark gray text on a dark background.

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What changed

Added a dark-mode specific override in css/themes.css:

body.dark .ui-autocomplete a {
color: #fff !important;
}

This increases selector specificity and restores proper contrast in dark mode without affecting light mode.

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Scope

• Affects only the search autocomplete dropdown in dark mode
• No changes to logic or behavior
• No impact on light theme

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Verification

• Enabled dark mode
• Searched for blocks (e.g., "note")
• Confirmed dropdown text is clearly readable
• Verified light mode remains unchanged

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Before

After

[github-actions]

✅ All Jest tests passed! This PR is ready to merge.

[zealot-zew]

i believe there's an open PR on this exact issue, (#5681) Please consider closing your PR to keep the reviewing easy.

[Ady0333]

i believe there's an open PR on this exact issue, (#5681) Please consider closing your PR to keep the reviewing easy.

Well okay!! I'll close my PR.