* Macros WIP
`helix_term::compositor::Callback` changed to take a `&mut Context` as
a parameter for use by `play_macro`
* Default to `@` register for macros
* Import `KeyEvent`
* Special-case shift-tab -> backtab in `KeyEvent` conversion
* Move key recording to the compositor
* Add comment
* Add persistent display of macro recording status
When macro recording is active, the pending keys display will be shifted
3 characters left, and the register being recorded to will be displayed
between brackets — e.g., `[@]` — right of the pending keys display.
* Fix/add documentation
* Add preview pane for fuzzy finder
* Fix picker preview lag by caching
* Add picker preview for document symbols
* Cache picker preview per document instead of view
* Use line instead of range for preview doc
* Add picker preview for buffer picker
* Fix render bug and refactor picker
* Refactor picker preview rendering
* Split picker and preview and compose
The current selected item is cloned on every event, which is
undesirable
* Refactor out clones in previewed picker
* Retrieve doc from editor if possible in filepicker
* Disable syntax highlight for picker preview
Files already loaded in memory have syntax highlighting enabled
* Ignore directory symlinks in file picker
* Cleanup unnecessary pubs and derives
* Remove unnecessary highlight from file picker
* Reorganize buffer rendering
* Use normal picker for code actions
* Remove unnecessary generics and trait impls
* Remove prepare_for_render and make render mutable
* Skip picker preview if screen small, less padding
* reverse the dependency between helix-tui and helix-view by moving a fiew types to view
* fix tests
* clippy and format fixes
Co-authored-by: Keith Simmons <keithsim@microsoft.com>