Error processing file

I encountered an error while working with a file: during editing, the program crashed while attempting to unwrap a value that was None

When navigating focus elements, the editor panics with:

thread 'main' panicked at crates/edit/src/tui.rs:1537:59: called Option::unwrap() on a None value

The issue is in the focus traversal loop:

focused_start = focused_start.borrow().parent.unwrap();

If a node has no parent and ptr::eq(focused_start, focus_well) doesn't catch it first, unwrap() panics.

Suggested fix:

focused_start = match focused_start.borrow().parent.clone() {
    Some(p) => p,
    None => break,
};