Request: Undo page delete

### What
Simple request: cmd+z (or ctrl+z) can UNDO a page delete.

### Why
It's happened to me pretty often that I've accidentally deleted a page, or deleted it then realized I wanted to pull out some other content. Currently, I have to go into my Deleted notes and dig around to find it. (It will usually not be at the top because of Pinned notes in the trash, and as far as I know it's not possible to search the trash either.)

### How
Should be self-explanatory I believe.

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Thanks for the great app!

The issue requests cmd+z or ctrl+z to undo a page deletion, avoiding manual recovery from Deleted notes. Start by locating the macOS page-delete and keyboard shortcut handling; done means a recently deleted page can be restored with the appropriate shortcut.

Written by the indexing model from the issue text.