Respect selection filter when adding intervals

[XiaoMigros]

Resolves: #32070

Note: design will only ever add a single note per chord to range selections. This differs from list selections, where multiple notes could be added.

[avvvvve]

@XiaoMigros Approved!

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Also, noting this because it seemed like a bug for a second, but then I realized it's because the selection filter is still active.

I expected the newly-added notes to be selected after running the 'add interval' operation (as happens when you start with a list selection), but since the selection filter is in effect, the bottom note stays selected and the top note gets selected (because the a new note was added to the chord, and now the 'Top note' filter is on because it wasn't showing before).

Screen.Recording.2026-02-09.at.11.29.57.AM.mov

For me, this just gets at something that always has felt a bit clunky about the selection filter to me: when you make a new selection, the selection filter is still in effect. When we have time I think it would still be nice to create a version of the selction filter that lets you press a button to "filter" the selection based on your filtering options. @bkunda @jessjwilliamson pinning the thought for another time!

[MarcSabatella]

FWIW, this has been a long-standing complaint against the selection filter. It's especially problematic if you use the filter to exclude voice 1 from a selection, because now you can't select anything anymore unless it happens to have content in other voices. So for example, trying to copy & paste voice 2 from one place to another fails at first because you can't select the destination until you remember to re-enable voice 1.

A design that handled all of this better would be welcome indeed!