Fixes this panic that I've been seeing in Slack:


[example](https://zed-industries.slack.com/archives/C04S6T1T7TQ/p1696530575535779)


```
thread 'main' panicked at 'assertion failed: opened_items.len() == project_paths_to_open.len()'
crates/workspace/src/workspace.rs:3628
<backtrace::capture::Backtrace>::create
<backtrace::capture::Backtrace>::new
Zed::init_panic_hook::{closure#0}
std::panicking::rust_panic_with_hook
std::panicking::begin_panic_handler::{{closure}}
std::sys_common::backtrace::__rust_end_short_backtrace
_rust_begin_unwind
core::panicking::panic_fmt
core::panicking::panic
<workspace::Workspace>::new_local::{closure#0}::{closure#0}
```

I believe it was caused by a window being closed immediately, while it
was still loading some paths. There was a mismatch in expectation
between the `workspace::open_items` function (which contains this
assertion), and the `Workspace::load_workspace` method. That later
method can return an empty vector if the workspace handle is dropped
while it is executing.

Release Notes:

- Fixed a crash when closing a Zed window immediately after opening it

TODO:
- [x] Add markdown rendering to channel chat
- [x] Unify (?) rendering logic between hover popover and chat
- [x] ~~Determine how to deal with document-oriented markdown like `#`~~
Unimportant until we want to do something special with `#channel`
- [x] Tidy up spacing and styles in chat panel

Release Notes:

- Added markdown rendering to channel chat
- Improved channel chat message style
- Fixed a bug where long chat messages would not soft wrap

This fixes some bugs in our following logic, due to our attempts to
prevent infinite loops when two people follow each other.

* Propagate all of leader's views to a new follower, even if those views
were originally created by that follower.
* Propagate active view changes to followers, even if the active view is
following that follower.
* Avoid redundant active view updates on the client.

Release Notes:

- Fixed bugs where it was impossible to follow someone into a view that
they previously following you into.

Release Notes:

- N/A

Release Notes:

- Fix clicking the notes icon when people are in the channel (preview
only)

Release Notes:

- Add user avatars to channel chat messages
- Group messages by sender
- Fix visual bugs in new chat and note buttons

Also, remove logic for implicitly marking chat messages as observed when
they are fetched. I think this is unnecessary, because the client always
explicitly acknowledges messages when they are shown.

Release Notes:

- Fixed a bug where chat messages were shown out of order (preview only)

Release Notes:

- Fixes a panic in vim when incrementing a non-number.

This PR adds a mechanism for notifying the client when a channel note
has been edited or a message has been changed.

TODO: 
- [x] Fix infinite loop when opening the chat panel
- [x] Switch to client-side ack model of observation detection
- [x] Add client-side-only change detection (e.g. for when a channel
note is open locally but not focused)
- [x] Review implementation / query performance.
- [x] Fix lack of ACK on restart for channel buffers
- [x] remove channel note opening on click
- [x] Fix channel messages sent while chat channel is in the background
not showing the channel as changed.

Release Notes:

- N/A

co-authored-by: max <max@zed.dev>

Co-authored-by: conrad <conrad.irwin@gmail.com>
Co-authored-by: max <max@zed.dev>

co-authored-by: Conrad <conrad.irwin@gmail.com>

co-authored-by: conrad <conrad.irwin@gmail.com>

co-authored-by: conrad <conrad.irwin@gmail.com>

Co-authored-by: Mikayla <mikayla@zed.dev>

Co-authored-by: Mikayla <mikayla@zed.dev>

Release Notes:

- Clicking on a channel in the sidebar will now join the channel and
open the notes
- If you join a channel that already shared projects, you will join the
projects automatically and follow the host.
- Clicking on the current channel in the sidebar will re-open the notes.
- Chat can now be accessed from the right click menu of channels.


- (probably not worth mentioning) Various improvements to hover states
and tooltips in the collab ui; and if you click on a channel while in
another call, confirm before switching.

co-authored-by: Max <max@zed.dev>

Co-authored-by: Max <max@zed.dev>

Release Notes:

- N/A

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

Reverts zed-industries/zed#3049

- Clicking on a channel name now joins the channel if you are not in it
- (or opens the notes if you are already there).
- When joining a channel, previously shared projects are opened
  automatically.
- If there are no previously shared projects, the notes are opened.

Release Notes:

- show host in the titlebar of shared projects
- clicking on faces in the titlebar will now always follow the person
(it used to toggle)
- clicking on someone in the channel panel will follow that person
- highlight the currently open project in the channel panel

- fixes a bug where sometimes following between workspaces would not
work

Release Notes:

- N/A

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

Co-authored-by: Mikayla <mikayla@zed.dev>

Also, start work on new timing for recording observed notes edits.

Co-authored-by: Mikayla <mikayla@zed.dev>

Co-authored-by: Mikayla <mikayla@zed.dev>

Prior to this change you could only follow across workspaces when you
were heading to the first window.

This PR mainlines the current state of new GPUI2-based UI from the
`gpui2-ui` branch.

Release Notes:

- N/A

---------

Co-authored-by: Nate Butler <iamnbutler@gmail.com>
Co-authored-by: Piotr Osiewicz <24362066+osiewicz@users.noreply.github.com>
Co-authored-by: Nate <nate@zed.dev>

Otherwise the spawn to resolve the additional edits never runs causing
autocomplete to never add imports automatically when clicking with the
mouse

Release Notes:

- Fixed auto-complete additional edits, such as auto-import, not
applying when selecting a completion with a mouse click.

Otherwise the spawn to resolve the additional edits never runs causing
autocomplete to never add imports automatically when clicking with the
mouse

Before this change if you joined a project without clicking on the
notification it would never disappear.

Fix a related bug where if you have more than one monitor, the
notification was only dismissed from one of them.