feat(ui): improve search bar visuals

[hanthor]

This PR improves the search bar visuals by:

• Adding a border that changes color when focused.
• Moving the 'Search' label to the border title.
• Enabling cursor blinking.

[Copilot]

Pull request overview

This PR enhances the search bar UI by adding a border with dynamic coloring on focus, repositioning the search label as a border title, and adjusting layout spacing. The changes migrate from using SetLabel to SetTitle for the InputField, add border styling with focus/blur handlers, and increase the filters area height to accommodate the new border.

Changes:

• Added theme colors for search border (SearchBorderColor) and focused border (SearchFocusBorderColor)
• Migrated search field from label-based to title-based approach with border styling
• Added focus/blur handlers to change border color dynamically (green when focused, white otherwise)
• Adjusted filters area height from 2 to 3 to accommodate the new border

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
internal/ui/theme/theme.go	Added SearchBorderColor and SearchFocusBorderColor fields with white and green defaults
internal/ui/components/search.go	Migrated from SetLabel to SetTitle, added border with focus/blur handlers, added counter padding
internal/ui/layout.go	Increased filters area height from 2 to 3 rows to accommodate the new border
internal/services/app.go	Updated Brewfile mode to use SetTitle instead of SetLabel

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[Copilot]

The SearchLabelColor field is no longer used after migrating from SetLabel to SetTitle. This field should be removed to avoid maintaining unused code. The search title now uses theme.TitleColor instead.

[Copilot]

The initialization of SearchLabelColor is no longer necessary since this field is not used anywhere in the codebase after migrating to SetTitle. This line should be removed along with the field declaration.