Fixes Z-1618. In the current state, this only works for line comments
such as `//` (and whatever's set in `{language}.toml` as a
line_comment).

Release Notes:

- Comments are now extended on new line.

This pull request introduces a new assistant panel to Zed that lets
users interact with OpenAI using their API key:

![CleanShot 2023-06-07 at 09 39
10@2x](https://github.com/zed-industries/zed/assets/482957/ba2a5830-9aeb-4c45-a182-a44d6a72675f)

After setting the key up, it will be saved to the keychain and
automatically loaded the next time the assistant panel is opened. The
key can be reset using `assistant: reset key`.

![CleanShot 2023-06-07 at 09 39
23@2x](https://github.com/zed-industries/zed/assets/482957/a6808bb0-0098-45ae-a2e3-f4d88472e626)

From there, users can type messages in a multi-buffer and hit
`cmd-enter` (`assistant: assist`) to stream assistant responses using
the OpenAI API. Responses can be canceled by hitting `escape`.

![CleanShot 2023-06-07 at 09 40
16@2x](https://github.com/zed-industries/zed/assets/482957/749779da-850e-4ad5-af04-74a3ca39f7ad)

Users can quote a selection from the active editor by hitting `cmd->`
(`assistant: quote selection`), which will embed the selected piece of
text in a Markdown fenced code block. Conversations with the assistant
are ephemeral at the moment, but can be easily copy/pasted:

![CleanShot 2023-06-07 at 09 50
33@2x](https://github.com/zed-industries/zed/assets/482957/b3386c10-4c51-4419-a0e0-517112ef6521)

Release Notes:

- Added a new assistant panel feature that enables interacting with
OpenAI using an API key. This replaces the previous experimental `ai:
assist` command that would work on any buffer. The experience is similar
to the one offered by ChatGPT with the added ability to edit, delete or
enhance previous messages. When hitting `cmd-enter`, the assistant will
start streaming responses from OpenAI. A response stream can be canceled
using `escape`. Moreover, the active editor's selection can be quoted in
the assistant panel using `cmd->`, which will automatically embed the
selected piece of text in a Markdown fenced code block.

Fixes
https://linear.app/zed-industries/issue/Z-2208/outline-view-doesnt-differentiate-between-overloaded-functions
Fixes
https://linear.app/zed-industries/issue/Z-2205/elixir-syntax-highlighting-not-working-properly-for-doc-attributes-and

This PR improves syntax highlighting and outline view in Elixir. It's
common to overload elixir functions, with many different versions of the
function for different patterns of parameters, so I updated the outline
view to show functions' parameters in Elixir. But if we showed functions
the same way in the *breadcrumbs*, it would take up too much space.

So I added a new capture in languages' `outline` queries called
`@context.extra`, which is included in the outline view, but not in
breadcrumbs.

Release Notes:

- Improved syntax highlighting of doc attributes and special macros in
Elixir
- Updated the outline view in Elixir to display function parameters, to
allow differentiating between function overloads.

Introduce a new capture in the outline query called 'context.extra', which
causes text to appear in the outline, but not in the breadcrumbs.

### Before

![Screen Shot 2023-06-06 at 2 32 46
PM](https://github.com/zed-industries/zed/assets/326587/036f1da3-19c6-4979-adc6-c3133f8d63dc)

### After

![Screen Shot 2023-06-06 at 2 32 08
PM](https://github.com/zed-industries/zed/assets/326587/6d4729db-b76a-4052-847e-fd9de346f194)

Release Notes:

* Improved the syntax highlighting of fenced code blocks in markdown.

This time I've added a `components` section to rust-toolchain.toml file
to explicitly require a rustfmt component. Fingers crossed.

This PR adds live reloading of Tree-sitter queries when running in debug
mode, similar to what we do for the themes. This way, you can change a
highlighting query or an outline query, and immediately see the result
in the app.

Release Notes:

- N/A

Reverts zed-industries/zed#2573

Add rust-toolchain.toml

Release Notes:

- N/A

Per conversation with Antonio, I've suggested enabling full LTO; right
now we use a crate-local ThinLTO, which does not inline function calls
across crates.

| Configuration    | Current main (788f97e) | Thin LTO  | Full LTO  |
|------------------|------------------------|-----------|-----------|
| Size in bytes    | 158806721              | 155868753 | 111115553 |
| % of `main` size | 100%                   | 98.14%    | 69.96%    |
| Size in bytes (no debug info) | 129186657 | 127942929 | 108281345 |

Previously, all static assets were embedded into Zed using a single
`RustEmbed` struct called `Assets`, which was in a crate of its own,
also called `assets`. Many crates depended on this crate. The problem
with this situation was that changing *any* static asset file caused
almost every crate in the codebase to need recompilation (because of
recursive dependencies on `assets`).

Now, most of the assets are embedded only into the top-level `zed`
crate. A few assets (such as settings JSON files and AI prompts) are
needed in lower-level crates such as `settings` and `ai`. For these,
I've created separate `RustEmbed` structs in those specific crates,
which embed those specific sub-folders of `assets`.

The result is that now, when you change a theme file, the only crate
that needs to recompile is `zed`.

Release Notes:

- N/A

Co-Authored-By: Nathan Sobo <nathan@zed.dev>

Co-Authored-By: Nathan Sobo <nathan@zed.dev>

Previously, project-specific settings were not discoverable. This PR
adds a `Zed > Preferences > Local Settings` application menu command
that creates a `.zed/settings.json` at the root of your current
worktree. This command works in both local and remote projects.

Limitations:

* Currently, if you have an empty project open, the command just shows a
notification that there are no folders open.
* The JSON-schema-based autocomplete is the same in local settings files
as in your main settings, even though not all settings can be locally
customized.

Release Notes:

- Added an application menu command - `Zed > Preferences > Local
Settings` for creating a folder-specific settings file.

Co-Authored-By: Nathan Sobo <nathan@zed.dev>

Co-Authored-By: Nathan Sobo <nathan@zed.dev>

Following https://github.com/zed-industries/zed/pull/2559 the project
panel entries become pretty wide again. This PR tries to mitigate that
and just make some general improvements to visual density in the project
panel.

- Reduces padding around items
- Removes top margin
- Slightly reduces the height of each item
- Fixes an issue where ignored files had the wrong color chevron

Release Notes:

- Improved density of the project panel and tidied up some visual
issues.

Z-1012

Release notes:
- Adjust indent of files in subdirectories.

Co-Authored-By: Julia Risley <julia@zed.dev>

Co-Authored-By: Julia Risley <julia@zed.dev>