chore(ai): avoid conflicting keybinding for opening chat window

ctrlcmd+shift+e is actually used already for the navigator. VS Code uses ctrlcmd+alt+i. So I used that as a keybinding for the chat view instead.

packages/ai-chat-ui/src/browser/ai-chat-ui-contribution.ts

@@ -52,7 +52,7 @@ export class AIChatContribution extends AbstractViewContribution<ChatViewWidget>
                 rank: 100
             },
             toggleCommandId: AI_CHAT_TOGGLE_COMMAND_ID,
-            toggleKeybinding: 'ctrlcmd+shift+e'
+            toggleKeybinding: 'ctrlcmd+alt+i'
         });
     }