agent: Fix inline assistant keymap in agent panel (#51117)

Fixes a bug that causes the new large agent panel message editor
overrides the ctrl-enter keyboard shortcut to trigger the inline
assistant, rather than sending a message

Release Notes:

- N/A *or* Added/Fixed/Improved ...

assets/keymaps/default-linux.json

@@ -819,7 +819,7 @@
     },
   },
   {
-    "context": "!ContextEditor > Editor && mode == full",
+    "context": "!ContextEditor && !AcpThread > Editor && mode == full",
     "bindings": {
       "alt-enter": "editor::OpenExcerpts",
       "shift-enter": "editor::ExpandExcerpts",

assets/keymaps/default-macos.json

@@ -882,7 +882,7 @@
     },
   },
   {
-    "context": "!ContextEditor > Editor && mode == full",
+    "context": "!ContextEditor && !AcpThread > Editor && mode == full",
     "use_key_equivalents": true,
     "bindings": {
       "alt-enter": "editor::OpenExcerpts",

assets/keymaps/default-windows.json

@@ -821,7 +821,7 @@
     },
   },
   {
-    "context": "!ContextEditor > Editor && mode == full",
+    "context": "!ContextEditor && !AcpThread > Editor && mode == full",
     "use_key_equivalents": true,
     "bindings": {
       "alt-enter": "editor::OpenExcerpts",