Expansion wide preset search

[David Healey]

I've (Claude) added searching across expansions to the preset browser. If no expansion is selected then it will search all expansions. If an expansion is selected then it will only search within that expansion, if you change the selection it will move the search to the newly selected expansion. PR.

I also added a FullPathSearch data property, similar to the FullPathFavorites one I added a few months ago so you can see exactly which expansion/bank/category a preset belongs to in the search results. Very useful if you have multiple presets with the same name.

I'll also implement a similar thing to make favourites work across expansions.