Shorten explanation when edit predictions are disabled for a language (#54808)

The current text is a bit wordy and puts the actually important
information at the end:

<img width="607" height="120" alt="image"
src="https://github.com/user-attachments/assets/26f998dd-1801-4e6c-a40c-acb58f8f3efc"
/>

The button already shows as disabled, so the text just needs to explain
why.

I don't think this affects accessibility, because a screen reader should
be able to tell that the button is disabled.

Self-Review Checklist:

- [ ] I've reviewed my own diff for quality, security, and reliability
- [ ] Unsafe blocks (if any) have justifying comments
- [ ] The content is consistent with the [UI/UX
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
- [ ] Tests cover the new/changed behavior
- [ ] Performance impact has been considered and is acceptable

Release Notes:

- N/A

crates/edit_prediction_ui/src/edit_prediction_button.rs

@@ -712,14 +712,16 @@ impl EditPredictionButton {
 
             match language_state.clone() {
                 Some((language, false)) => {
-                    menu = menu.item(
-                        entry
-                            .disabled(true)
-                            .documentation_aside(DocumentationSide::Left, move |_cx| {
-                                Label::new(format!("Edit predictions cannot be toggled for this buffer because they are disabled for {}", language.name()))
-                                    .into_any_element()
-                            })
-                    );
+                    menu = menu.item(entry.disabled(true).documentation_aside(
+                        DocumentationSide::Left,
+                        move |_cx| {
+                            Label::new(format!(
+                                "Edit predictions are disabled for {}",
+                                language.name()
+                            ))
+                            .into_any_element()
+                        },
+                    ));
                 }
                 Some(_) | None => menu = menu.item(entry),
             }