Co-Authored-By: Mikayla Maki <mikayla.c.maki@gmail.com>

This adds tree-sitter grammars for both Elm and GLSL, with injections
for GLSL embedded within Elm. It also adds an `outline.scm` for Elm,
though limitations in the tree-sitter grammar meant that I wasn't able
to get it looking exactly how I'd have liked.

In particular, it wasn't clear how to nicely annotate functions in the
outline as being functions, or how to prevent the fields of a record
declaration from being increasingly indented.


![image](https://github.com/zed-industries/zed/assets/285821/544bc00b-3bfc-4ec7-be9d-764b9f0292ab)

![image](https://github.com/zed-industries/zed/assets/285821/74e57e95-bf87-4989-ae29-a2f625141bcf)

![image](https://github.com/zed-industries/zed/assets/285821/9e283c78-66d5-4c15-9827-1b5b446cdc37)

fixes https://github.com/zed-industries/community/issues/598

Release Notes:
- Added syntax highlighting for the Elm and GLSL languages

Co-Authored-By: Mikayla Maki <mikayla.c.maki@gmail.com>

Co-Authored-By: Nate Butler <iamnbutler@gmail.com>

Co-Authored-By: Julia <30666851+ForLoveOfCats@users.noreply.github.com>

@mikayla-maki for 👀 

[This PR added in the ability to rename a file via
`enter`](https://github.com/zed-industries/zed/pull/2784). Previously,
`enter` was used to both open a file and confirm a rename, so this PR
changes the opening of a file to use `space`, which is what VS Code
uses. It also makes a bit more sense because now `enter` is just used to
start a rename and confirm the rename, vs being used for 2 different
actions.

N/A on the release notes, as I adjusted the release note in the
previously-tagged PR.

Release Notes:

- N/A

Follow-up to https://github.com/zed-industries/zed/pull/2777
Refs https://github.com/zed-industries/community/issues/1770

In this PR, I reworked the way that git statuses are retrieved. In a
huge repository like `WebKit`, the really slow part of computing a list
of git statuses is the *unstaged* portion of the diff. For the *staged*
diff, `git` can avoid comparing the contents of unchanged directories,
because the index contains hashes of every tree. But for the *unstaged*
portion, Git needs to compare every file in the worktree against the
index. In the common case, when there are no changes, it's enough to
check the `mtime` of every file (because the index stores the mtimes of
files when they are added). But this still requires an `lstat` call to
retrieve each file's metadata.

I realized that this is redundant work, because the worktree is
*already* calling `lstat` on every file, and caching their metadata. So
in this PR, I've changed the `Repository` API so that there are separate
methods for retrieving a file's *staged* and *unstaged* statuses. The
*staged* statuses are retrieved in one giant batch, like before, to
reduce our git calls (which also have an inherent cost). But the
`unstaged` statuses are retrieved one-by-one, after we load files'
mtimes. Often, all that's required is an index lookup, and an mtime
comparison.

With this optimization, it once again becomes pretty responsive to open
`WebKit` or `chromium` in Zed.

Release Notes:

- Optimized the loading of project file when working in very large git
repositories

Release Notes:

- Added a default keybinding for using enter to rename files in the
project panel

One of the problems we had is that the status_bar shows a gap between
items, and we want to not add an additional gap for an invisible status
indicator.

Release Notes:

- Fixes a crash when SelectAllMatches action was called on no matches

Enable non-literal matching so that directory paths match
all files contained within them.

Fix left dragging cascade
WIP: Implement right dragging, WIP: use drag end events to set and reset state around initial flex orientation

Further improves terminal navigation with cmd+click, now allowing to
open paths starting with `~` (if they are present otherwise) and
focusing project panel with highlighted entry for the directories
opened.

Release Notes:

- Further improves terminal navigation with cmd+click, now allowing to
open paths starting with `~` (if they are present otherwise) and
focusing project panel with highlighted entry for the directories
opened.

This is the second most common remaining complaint (after :w not
working).

Fixes: zed-industries/community#409

Closes
https://linear.app/zed-industries/issue/Z-2689/huge-slowdown-when-working-in-large-git-repositories-like-webkit
Closes https://github.com/zed-industries/community/issues/1770

In large git repositories (like Webkit), `git status` can be very slow.
And our current approach of retrieving git statuses (one by one as we
load paths), causes catastrophic slowdowns in these repos. This PR
further optimizes our retrieval of git statuses (started in
https://github.com/zed-industries/zed/pull/2728), so that when scanning
a directory, we only load git statuses once, in a single batch, at the
beginning of the scan.

There is still an initial lag when opening `WebKit` in Zed, while the
initial git status runs. But once this call completes, everything is
fast. Let's come back to this problem later.

For now, this makes Zed's directory scanning massively more efficient,
even in the case of normal-sized repos like `zed`. The git status code
was a huge percentage of zed's CPU usage when launching. Here is that
code, highlighted in a flamegraph before and after this change:

Before:

![before](https://github.com/zed-industries/zed/assets/326587/627012f2-6131-44ac-95c2-ea4a4531cb24)

After:

![after](https://github.com/zed-industries/zed/assets/326587/a11a3e1b-e925-4bff-a421-ea71cb4de85d)


Release Notes:

- Fixed a bug where project paths took a very long time to load when
working in large git repositories
([#1770](https://github.com/zed-industries/community/issues/1770))

In big buffers, when I press `cmd-a`, the view gets scrolled to the very
bottom.
Usually it's now that I want, I can scroll to bottom with `cmd-down`
separately, and selecting all text is used for copy-pasting it
somewhere, no need to scroll anywhere for that — I can get back to the
same place later.

Release Notes:

- Removed the scroll to the end of the editor after `editor::SelectAll`
action