Filter entities in the UI (part 1): Introduce a filter widget

[abey79]

Related

• Part of Project: filtering entities in the UI (first iteration) #8586
• Part of a series of PR:
  • Filter entities in the UI (part 0): Make CustomContent more useful #8645
  • Filter entities in the UI (part 1): Introduce a filter widget #8652
  • Filter entities in the UI (part 2): Introduce entity filtering in the time panel #8654
  • Filter entities in the UI (part 3): Move action to a menu in the blueprint panel and keep default blueprint when using heuristics #8672
  • Filter entities in the UI (part 4): Add entity filtering in the blueprint tree #8706
  • Filter entities in the UI (part 5): Add snapshot tests for the blueprint tree #8728
  • Filter entities in the UI (part 6): Refactor re_blueprint_tree and add more tests #8795
  • Filter entities in the UI (part 7): Refactor and optimize re_time_panel and add more tests #8863
  • Filter entities in the UI (part 8): Make the query semantics more powerful #8886
  • Filter entities in the UI (part 9): Support / in queries #8933

What

This PR introduce a filter widget with the following feature:

• the widget acts as a toggle: it's either on or off
• when off, it's just a right-aligned icon and a (more-or-less) regular section title
• when on, the title is replaced by a text edit
• each time it's toggled on, the filter widget maintains a session id, for the client code to use to cache filter-session-specific data (e.g. collapsedness state)
• this also include a FilterMatcher, which is an helper object that performs the actual filtering
  NOTE: this will surely be entirely rewritten as we improve on the filter semantics
• helper function to create a properly formatted matched text (with the matching parts highlighted)

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Result	Commit	Link	Manifest
✅	ea1e923	https://rerun.io/viewer/pr/8652	+nightly +main

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[Wumpf]

nice!
there seems to be some mixup between empty string and None matchers that needs to be cleaned up

[abey79]

Arf yeah I switched last minute to "" matching nothing instead of everything (upon Katya's suggestion during the demo), and clearly I didn't cleanup properly.

[Wumpf]

thanks!