[authoring] editor improvements

[Rich Burdon]

• when switching documents the scroll position is incorrectly preserved from the previous doc (remember position per document)
• when switching to editor, decoration parsing is visible (jitter)
• don't expand link text if moving up/down through document
• manage global key bindings (i.e., show all in shortcuts dialog)
• read/edit/source modes; fullscreen reading mode (larger font)
• comments/bookmarks (range)
• styling
  • reconcile class defs with tailwind theme
  • search panel (panels in general) styling; search may be off screen
    • rewrite as react component replace buttons with phosphor icons
    • pressing enter in search box should go to next
    • escape to close
  • consolidate themes from extensions?
• outliner
• table editor (style edit view in monospace); auto expand other rows to align columns