It's not possible to not show notes in a trash folder in the search result, unless this is coded in core. A plugin cannot change the default search query run by Joplin core.
I'm in a process of writing a trash plugin. The problem is not the code, but usability stuff. (I'm really bad with UX and UI.) I can think of 2 methods how to specify the trash notebook:
- create a
Trash (Plugin)
folder the first time the plugin is used - allow people to select a folder to be the Trash folder by right-clicking on the folder and click on a context menu item
Set as trash bin
orSet as rubbish bin
Both options would allow to change the name later and/or move it into any other notebook.
I might just create a poll on the forum.
P.S.: Poll: Trash bin plugin