Add setting to disable all AI features (#34896)

https://github.com/user-attachments/assets/674bba41-40ac-4a98-99e4-0b47f9097b6a


Release Notes:

- Added setting to disable all AI features

crates/inline_completion_button/src/inline_completion_button.rs

@@ -1,5 +1,5 @@
 use anyhow::Result;
-use client::{UserStore, zed_urls};
+use client::{DisableAiSettings, UserStore, zed_urls};
 use copilot::{Copilot, Status};
 use editor::{
     Editor, SelectionEffects,
@@ -72,6 +72,11 @@ enum SupermavenButtonStatus {
 
 impl Render for InlineCompletionButton {
     fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
+        // Return empty div if AI is disabled
+        if DisableAiSettings::get_global(cx).disable_ai {
+            return div();
+        }
+
         let all_language_settings = all_language_settings(None, cx);
 
         match all_language_settings.edit_predictions.provider {