Automatically resize tree browser panel while navigating

[AdrianoKF]

The initial width of the navigator panel is based on the collapsed subtree:

However, when expanding subtrees, the panel width stays fixed, leading to illegible text:

Resizing the terminal window or opening a file properly adjusts the panel width.

Instead of waiting for these events, the panel should be resized accordingly whenever the user navigates the file tree, so that new elements are always visible (maybe up to a maximum width - introducing horizontal scrolling?)