Clean up context menus

[daviddossett]

Context menus, especially in editors and notebooks, have grown substantially in size and variety as VS Code has evolved. There are inconsistencies to address (e.g. Share is in a different place in different menus) and organizational improvements that could be made.

Here's a rough sketch that looks at:

• Folding large sections like Go to into their own submenu
• Moving Copy / Share / Copilot groups to the bottom so they are consistent across different menus

[emsaks]

Maybe merge the Goto and Peek options - have a clickable 'peek' icon on the Goto entry to peek instead of opening new window.

Also, the copy/paste/cut can be shrunk into one row of icons like in the Windows 11 Explorer context menu.