csv_preview: #6 Refine row filtering UI

[HalavicH]

Objective

Improve UI of row filtering (icons & popup), add intuitive controls, search among options.
Filter icons improvement

A bugfix of bug showing incorrect number of occurances when multiple filters were stacked together

Solution

Implemented popover with variable height list which shows filter options with checked/unchecked status and counts.
Grows automatically up to 60% viewport height, after - scrollbar appears

Testing

Tested using few fixtures: single line, multiline
With long and short list of entries (scrolling)
With multiple filters stacked together (filter chain)
No platform specific changes

Self-Review Checklist:

• I've reviewed my own diff for quality, security, and reliability
• Unsafe blocks (if any) have justifying comments
• The content adheres to Zed's UI standards (UX/UI and icon guidelines)
• Tests cover the new/changed behavior
• Performance impact has been considered and is acceptable

Showcase

Before:

After:

First filter application

Second filter application

Search in filter

Tooltip over cell which allow to copy content

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Release Notes:

• Refined CSV preview UI

[HalavicH]

Closing as it was split into #60995 #61127 #61138 #61769 #61796