Allow search to show subdecks if they match the searched term

[ShridharGoel]

Purpose / Description

This addresses a bug where searching for a sub-deck in the deck picker would fail to return the expected deck if one of its ancestor decks was collapsed. For example, if a user has the deck structure Science::Math::Algebra::Group and the Math deck is collapsed, searching for "Group" would not yield the Science::Math::Algebra::Group deck. This is not ideal, as users should not need to remember the collapsed state of parent decks when searching for a specific sub-deck.

Fixes

• Fixes Search should show hidden subdeck if it match #18287

Approach

When searching, we'll ignore collapsed state and always search sub-decks.

How Has This Been Tested?

Manual testing + unit tests.

Demo

Screen_recording_20250511_010042.webm

Checklist

• You have a descriptive commit message with a short title (first line, max 50 chars).
• You have commented your code, particularly in hard-to-understand areas
• You have performed a self-review of your own code
• UI changes: include screenshots of all affected screens (in particular showing any new or changed strings)
• UI Changes: You have tested your change using the Google Accessibility Scanner

[Arthur-Milchior]

I'd appreciate one extra test, but it clearly solve the issue so fine by me

[Arthur-Milchior]

Actually, I know see another problem with your code.

If you search for "algebra", then the little icon on the left of the deck shows that "science" is not collapse, "math" is collapsed, and "algebra" is not collapsed.

The button on the left of "algebra" will allow to indeed collapse on uncollapse subdecks. The button on the left of "science" and "math" will be ignored.

I believe we should remove the buttons whose action are ignored. That is, "science" and "math" should not show any button to collapse/uncollapse.

In an ideal world, I'd keep them, if I were certain the user would understand that the impact of those button would be seen one the search is removed. However, this behavior would be very confusing, so I believe we should just remove it.

This can be left as a TODO, given that your PR is already an improvement over the current state of the codebase, I'm fine merging it once the extra tests are added

[Arthur-Milchior]

Once the issue is created and the TODO contains an explanation instead of a link I'm fine merging it