Fix ctrl-delete keybind in the terminal (#51726)

showkey in Ghostty, iTerm2, and Terminal.app reports ctrl-delete as
`<ESC>[3;5~`.

I tested this keybind on macOS, where fish_key_reader correctly
interprets it as ctrl-delete.

Closes #51725

Before you mark this PR as ready for review, make sure that you have:
- [ ] Added a solid test coverage and/or screenshots from doing manual
testing
- [ ] Done a self-review taking into account security and performance
aspects
- [ ] Aligned any UI changes with the [UI
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)

Release Notes:

- Fixed ctrl-delete keybind in the terminal

---------

Co-authored-by: Jakub Konka <kubkon@jakubkonka.com>

assets/keymaps/default-linux.json

@@ -1209,7 +1209,7 @@
       "alt-b": ["terminal::SendText", "\u001bb"],
       "alt-f": ["terminal::SendText", "\u001bf"],
       "alt-.": ["terminal::SendText", "\u001b."],
-      "ctrl-delete": ["terminal::SendText", "\u001bd"],
+      "ctrl-delete": ["terminal::SendText", "\u001b[3;5~"],
       // Overrides for conflicting keybindings
       "ctrl-b": ["terminal::SendKeystroke", "ctrl-b"],
       "ctrl-c": ["terminal::SendKeystroke", "ctrl-c"],

assets/keymaps/default-macos.json

@@ -1278,7 +1278,7 @@
       "alt-right": ["terminal::SendText", "\u001bf"],
       "alt-b": ["terminal::SendText", "\u001bb"],
       "alt-f": ["terminal::SendText", "\u001bf"],
-      "ctrl-delete": ["terminal::SendText", "\u001bd"],
+      "ctrl-delete": ["terminal::SendText", "\u001b[3;5~"],
       // There are conflicting bindings for these keys in the global context.
       // these bindings override them, remove at your own risk:
       "up": ["terminal::SendKeystroke", "up"],