gpui: Add line_clamp to truncate text after a specified number of lines (#23058)

Release Notes:

- N/A

Add this feature for some case we need keep 2 or 3 lines, but truncate.
For example the blog post summary.

- Added `line_clamp` method.
    Ref: https://tailwindcss.com/docs/line-clamp


## Break changes:

- Renamed `gpui::Truncate` to `gpui::TextOverflow` to match
[CSS](https://developer.mozilla.org/en-US/docs/Web/CSS/text-overflow).
- Update `truncate` style method to match [Tailwind
CSS](https://tailwindcss.com/docs/text-overflow) behavior:

    ```css
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    ```
<img width="538" alt="image"
src="https://github.com/user-attachments/assets/c69c4213-eac9-4087-9daa-ce7afe18c758"
/>


## Show case

<img width="816" alt="image"
src="https://github.com/user-attachments/assets/e0660290-8042-4954-b93c-c729d609484a"
/>

![CleanShot 2025-01-13 at 17 22
05](https://github.com/user-attachments/assets/38644892-79fe-4254-af9e-88c1349561bd)

## Describe changes

The [second
commit](6b41c2772f)
for make sure text layout to match with the line clamp. Before this
change, they may wrap many lines in sometimes. And I also make
line_clamp default to 1 if we used `truncate` to ensure no wrap.

> TODO: There is still a tiny detail that is not easy to fix. This
problem only occurs in the case of certain long words. I will think
about how to improve it later. At present, this has some flaws but does
not affect the use.

crates/gpui/src/text_system.rs

@@ -374,12 +374,15 @@ impl WindowTextSystem {
         font_size: Pixels,
         runs: &[TextRun],
         wrap_width: Option<Pixels>,
+        line_clamp: Option<usize>,
     ) -> Result<SmallVec<[WrappedLine; 1]>> {
         let mut runs = runs.iter().filter(|run| run.len > 0).cloned().peekable();
         let mut font_runs = self.font_runs_pool.lock().pop().unwrap_or_default();
 
         let mut lines = SmallVec::new();
         let mut line_start = 0;
+        let mut max_wrap_lines = line_clamp.unwrap_or(usize::MAX);
+        let mut wrapped_lines = 0;
 
         let mut process_line = |line_text: SharedString| {
             let line_end = line_start + line_text.len();
@@ -430,9 +433,14 @@ impl WindowTextSystem {
                 run_start += run_len_within_line;
             }
 
-            let layout = self
-                .line_layout_cache
-                .layout_wrapped_line(&line_text, font_size, &font_runs, wrap_width);
+            let layout = self.line_layout_cache.layout_wrapped_line(
+                &line_text,
+                font_size,
+                &font_runs,
+                wrap_width,
+                Some(max_wrap_lines - wrapped_lines),
+            );
+            wrapped_lines += layout.wrap_boundaries.len();
 
             lines.push(WrappedLine {
                 layout,