configure_v3: improve quick search label

[brliron]

In advanced mode, the "quick filter" field should be called "search" instead, and having a magnifying glass icon would probably help.

Maybe having this search label and/or the icon be over the field, instead of on its side, would also help? Like in this example from the Windows explorer (French screenshot, the text means "Search in: this computer")

There's also this example from Github:

And this one from Discord