Fix ctrl-enter opening inline-assistant in assistant text threads (#29313)

Closes: https://github.com/zed-industries/zed/issues/24501

This has been broken for a while on linux (at least since Feb 8th!) for Assistant1.
It is also broken for Text Threads in Assitant2 (on macos and linux).

This should fix both.

Potentially related:
- https://github.com/zed-industries/zed/pull/29107

Release Notes:

- Fix for `ctrl-enter` shortcut in Assistant text threads incorrectly
opening inline assist instead of triggering Send.

Co-authored-by: Conrad Irwin <conrad@zed.dev>

assets/keymaps/default-linux.json

@@ -675,7 +675,7 @@
     }
   },
   {
-    "context": "Editor && mode == full",
+    "context": "!ContextEditor > Editor && mode == full",
     "bindings": {
       "alt-enter": "editor::OpenExcerpts",
       "shift-enter": "editor::ExpandExcerpts",

assets/keymaps/default-macos.json

@@ -738,7 +738,7 @@
     }
   },
   {
-    "context": "Editor && mode == full",
+    "context": "!ContextEditor > Editor && mode == full",
     "use_key_equivalents": true,
     "bindings": {
       "alt-enter": "editor::OpenExcerpts",