Simplify Zed's collaboration system by:
- Only allowing member management on root channels.
- Disallowing moving sub-channels between different roots.
- Disallowing public channels nested under private channels.

This should make the mental model easier to understand, and makes it
clearer
who has what access. It is also significantly simpler to implement, and
so
hopefully more performant and less buggy.

Still TODO:
- [x] Update collab_ui to match.
- [x] Fix channel buffer tests.

Release Notes:

- Simplified channel membership management.

- Fail faster on serialization failure
- Move expensive participant update out of transaction

Release Notes:

- Fixed creating/moving channels in busy workspaces

One of the complaints of users on our first Hack call was that the error
messages you got when channel joining failed were not great.

This aims to fix that specific case, and lay the groundwork for future
improvements.

It adds two new methods to anyhow::Error

* `.error_code()` which returns a value from zed.proto (or
ErrorCode::Internal if the error has no specific tag)
* `.error_tag("key")` which returns the value of the tag (or None).

To construct errors with these fields set, you can use a builder API
based on the ErrorCode type:

* `Err(ErrorCode::Forbidden.anyhow())`
* `Err(ErrorCode::Forbidden.message("cannot join channel").into())` - to
add any context you want in the logs
* `Err(ErrorCode::WrongReleaseChannel.tag("required", "stable").into())`
- to add structured metadata to help the client handle the error better.


Release Notes:

- Improved error messaging when channel joining fails.

Release Notes:

- This fixes a panic that occurs when someone was using Vim mode and
typing umlauts into the command palette. E.g: `:%s/impërt`

We saw stack traces in our #panic channel pop up that failed on this
line:

https://github.com/zed-industries/alacritty/blob/33306142195b354ef3485ca2b1d8a85dfc6605ca/alacritty_terminal/src/event_loop.rs#L323-L324

With this message:

thread 'PTY reader' panicked at 'called `Result::unwrap()` on an `Err`
value: Os { code: 9, kind: Uncategorized, message: "Bad file descriptor"
}'

/Users/administrator/.cargo/git/checkouts/alacritty-afea874b09a502a5/3330614/alacritty_terminal/src/event_loop.rs:324

We don't know how to reproduce the error. It doesn't seem related to the
number of open PTY handles, because `openpty` itself didn't fail. We can
only assume that something went wrong between `openpty` and the setup of
the polling.

Since Alacritty itself changed its polling mechanism significantly by
switching from `mio` to `polling`
(https://github.com/alacritty/alacritty/pull/6846) we upgraded with the
hope that this will fix the bug.

Release Notes:

- Upgraded alacritty_terminal to newest version in order to hopefully
fix a rare panic that can occur when starting a new terminal.

Sometimes Cocoa calls app delegate methods (notably the display link)
while we're calling Cocoa methods. This causes a deadlock unless we
are careful to run cocao methods while we're not holding our internal
locks

Release Notes:

- Fixed a crash when opening the MacOS Save As dialogue.

Release Notes:

- Fixed a panic in calculating remote cursor positions

After the general release we saw a number of crashes due to a SEGFAULT
inside the
System::new() method apparently relating to refreshing the user list.

As we do not need the user list, and the similar code in the telemtry
create is not crashing,
do less work for now.

Release Notes:

- Fixed a crash when opening the feedback modal

Reverts zed-industries/zed#4236

This causes an infinite loop when opening the language server logs

This PR updates the docs to make it clearer that macOS Sonoma is
supported.

Release Notes:

- N/A

Since our last measurements, startup time in Zed had regressed quite
significantly. This was due to several issues:

- We were loading IBMPlex, which we're not really using in the UI.
- Images were being parsed in the foreground, thus blocking the main
thread
- Language models (for semantic index and assistant) were being loaded
in the foreground, thus blocking the main thread
- Interaction with the keychain was blocking the main thread

In addition to these, with this pull request we will now deserialize the
items for a pane in parallel, as opposed to doing so sequentially.

All combined, when running the zed binary directly this brings startup
time from ~350ms to ~210ms on my machine.

Release Notes:

- Improved startup time.

This fixes https://github.com/zed-industries/community/issues/2442 for
me.

Previously, the tab bar buttons would stay when the chat panel was
opened (and received focus) until something else was drawn (or caused a
render?)

With this change, the tab bar buttons are only shown if the pane was
focus.

I'm not sure about the side-effects of this, but the toolbar still seems
to work fine.

### Before


https://github.com/zed-industries/zed/assets/1185253/24b56e51-467b-4a09-909f-72ee6f76f32c

### After



https://github.com/zed-industries/zed/assets/1185253/18865f49-d00e-453a-8a38-aee15f06beb8



### Release Notes:

- (Added|Fixed|Improved) ...
([#<public_issue_number_if_exists>](https://github.com/zed-industries/community/issues/<public_issue_number_if_exists>)).

[[PR Description]]

Release Notes:

- N/A

This time around, we address the flicker seen in #3857 by querying the active item (that might've just been added),
as it knows whether it has focus even if the parent Pane does not.

Co-authored-by: Thorsten <thorsten@zed.dev>

Co-Authored-By: Mikayla Maki <mikayla@zed.dev>

We recently doubled the size of the `ELEMENT_ARENA` after someone ran
into a panic due to the arena running out of space.

This adds some logging so that we can hopefully develop a better
understanding of when the element area's allocation is elevated.

Release Notes:

- N/A

This fixes https://github.com/zed-industries/community/issues/2442 for
me.

Previously, the tab bar buttons would stay when the chat panel was
opened (and received focus) until something else was drawn (or caused a
render?)

With this change, the tab bar buttons are only shown if the pane was
focus.

I'm not sure about the side-effects of this, but the toolbar still seems
to work fine.

This fixes the performance problem we saw in
https://github.com/zed-industries/community/issues/2405.

In a trace we could see that if a font is missing we'd constantly look
it up and never cache that it's missing.

This changes that and does cache the font-is-missing result.

Drawback is that one would need to restart Zed after installing a
missing font that was configured in settings. That seems acceptable for
now, though.

Release Notes:

- Improved rendering performance when configured fonts are missing on
the system.

We recently doubled the size of the `ELEMENT_ARENA` after someone ran
into a panic due to the arena running out of space.

This adds some logging so that we can hopefully develop a better
understanding of when the element area's allocation is elevated.

Co-authored-by: Antonio <antonio@zed.dev>

This fixes the performance problem we saw in https://github.com/zed-industries/community/issues/2405.

In a trace we could see that if a font is missing we'd constantly look
it up and never cache that it's missing.

This changes that and does cache the font-is-missing result.

Drawback is that one would need to restart Zed after installing a
missing font that was configured in settings. That seems acceptable for
now, though.

Co-authored-by: Antonio <antonio@zed.dev>

This fixes a panic we just saw on nightly. It's the first time we see
this panic, so I think it's pretty safe to assume having twice as much
capacity will fix it.

Release Notes:

- Fixed a crash that could sometimes occur when the window contained
lots of graphical elements.

This fixes a panic we just saw on nightly. It's the first time we
see this panic, so I think it's pretty safe to assume having twice as
much capacity will fix it.

I want to immediately archive the `keymaps` repo tomorrow. This is the
only change that needs to be brought over.

Release Notes:

- N/A

This PR does some cleanup of the `gpui` docs, making sure we're linking
things appropriately and following good Rust documentation style.

Release Notes:

- N/A

This PR fixes a bug in GPUI where the observation API would not be
triggered if a focus event caused a `notify()`

Release Notes:

- N/A

This PR adds a `CODE_OF_CONDUCT.md` that links out to the existing code
of conduct on the Zed site.

The link in the file is currently a dead link, but will work once the
new site goes live tomorrow.

Release Notes:

- N/A

This PR balances the headings in the README.

Release Notes:

- N/A

This PR updates the README by removing the TODO items and linking out to
the contributing docs.

Release Notes:

- N/A

* Fixed jumping of list item when the separator appeared and
disappeared.
* Fixed a bug where the selection got into a valid state when updating
the matches

Release Notes:

- Fixed an issue where the file finder's selection got into a state
where nothing was selected after filtering the matches.