Add missing panels to View menu (#60356)

# Objective

Ensure that all existing panels have corresponding menu items in the
"View" menu. I was onboarding a friend to Zed yesterday that was having
a hard time figuring out how to interact with the Agent. Although he did
open the "View" menu, I noticed that the Agent panel item was missing
from there, making it hard for new users to discover it exists.

## Solution

* Add both "Agent Panel" and "Git Panel" entries to the menu items for
the "View" app menu.
* Update the action used for the "Terminal Panel" menu item from
`terminal_panel::ToggleFocus` to `terminal_panel::Toggle` to ensure we
display a shortcut for this menu item.
* Another valid option would be to update the default keymap to use
`terminal_panel::ToggleFocus` instead but that would probably break
existing user's expectations that the default shortcut toggles the
terminal panel, instead of toggling its focus.
* Introduce `zed_actions::git_panel` to be able to extract its
`ToggleFocus` action, following the existing pattern.

### Next Steps

It's worth noting that, even though there's now an "Agent Panel" item
mapped to the `assistant::ToggleFocus` action, its default keybinding is
not displayed (at least on macOS), because of the way it's defined as
`cmd-?` . Using `cmd-shift-/` instead doesn't work, so we'll likely have
to update `MacKeyboardMapper` to allow mapping between shifted and
unshifted keys equivalent, that is, when `?` is detected, it is able to
determine that, in the user's layout that is the result of `shift-/`.

## Testing

Manually tested, screenshots can be seen in the "Showcase" section.

## Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [ ] Unsafe blocks (if any) have justifying comments
- [ ] The content adheres to Zed's UI standards
([UX/UI](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
and
[icon](https://github.com/zed-industries/zed/blob/main/crates/icons/README.md)
guidelines)
- [ ] Tests cover the new/changed behavior
- [ ] Performance impact has been considered and is acceptable

## Showcase

<details>
  <summary>Before</summary>

<img width="488" height="946" alt="CleanShot 2026-07-03 at 14 24 35@2x"
src="https://github.com/user-attachments/assets/58b0497c-2929-4da3-86b6-a2e0ce0c5ca4"
/>

</details>

<details>
  <summary>After</summary>

<img width="524" height="1116" alt="CleanShot 2026-07-03 at 14 24 59@2x"
src="https://github.com/user-attachments/assets/8e2c6320-97ad-4620-b595-182f6d0ded81"
/>

</details>

---

Release Notes:

- Added "Agent Panel" and "Git Panel" items to the "View" menu
3cbe4c298eDino committed on 7/7/2026, 2:38:47 PM· committed by GitHubparentbc29bcf
3 files changedLine totals unavailable