gpui: Add truncate and text_ellipsis to TextStyle (#14850)

Release Notes:

- N/A

Ref issue #4996

## Demo

```
cargo run -p gpui --example text_wrapper 
```



https://github.com/user-attachments/assets/a7fcebf7-f287-4517-960d-76b12722a2d7

---------

Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>

crates/language_model/src/provider/anthropic.rs

@@ -518,6 +518,7 @@ impl ConfigurationView {
             underline: None,
             strikethrough: None,
             white_space: WhiteSpace::Normal,
+            truncate: None,
         };
         EditorElement::new(
             &self.api_key_editor,

crates/language_model/src/provider/google.rs

@@ -403,6 +403,7 @@ impl ConfigurationView {
             underline: None,
             strikethrough: None,
             white_space: WhiteSpace::Normal,
+            truncate: None,
         };
         EditorElement::new(
             &self.api_key_editor,

crates/language_model/src/provider/open_ai.rs

@@ -460,6 +460,7 @@ impl ConfigurationView {
             underline: None,
             strikethrough: None,
             white_space: WhiteSpace::Normal,
+            truncate: None,
         };
         EditorElement::new(
             &self.api_key_editor,