Implement pretty TypeScript errors (#42494)

Closes #7844

This change uses tree-sitter highlights as a method of showing
typescript errors prettily, keeping regex as simple as possible:

<img width="832" height="446" alt="Screenshot 2025-11-11 at 3 40 24 PM"
src="https://github.com/user-attachments/assets/0b3b6cf1-4d4d-4398-b89b-ef5ec0df87ec"
/>

It covers three main areas:

1. Diagnostics

Diagnostics are now rendered with language-aware typescript, by
providing the project's language registry.

2. Vtsls

The LSP provider for typescript now implements the
`diagnostic_message_to_markdown` function in the `LspAdapter` trait, so
as to provide Diagnostics with \`\`\`typescript...\`\`\`-style code
blocks for any selection of typescript longer than one word. In the
single-word case, it simply wraps with \`\`

3. Typescript's `highlights.scm`

`vtsls` doesn't provide strictly valid typescript in much of its
messaging. Rather, it returns a message with snippets of typescript
values which are invalid. Tree-sitter was not properly highlighting
these snippets because it was expecting key-value formats. For instance:
```
type foo = { foo: string; bar: string; baz: number[] }
```
is valid, whereas simply
```
{ foo: string; bar: string; baz: number[] }
```
is not.

Therefore, highlights.scm needed to be adjusted in order to
pattern-match on literal values that might be returned from the vtsls
diagnostics messages. This was done by a) identifying arrow functions on
their own, and b) augmenting the `statment_block` pattern matching in
order to match on values which were clearly object literals.

This approach may not be exhaustive - I'm happy to work on any
additional cases we might identify from `vtsls` here - but hopefully
demonstrates an extensible approach to making these messages look nice,
without taking on the technical burden of extensive regex.

Release Notes:

- Show pretty TypeScript errors with language-aware Markdown.

crates/editor/src/editor.rs

@@ -117,8 +117,9 @@ use language::{
     AutoindentMode, BlockCommentConfig, BracketMatch, BracketPair, Buffer, BufferRow,
     BufferSnapshot, Capability, CharClassifier, CharKind, CharScopeContext, CodeLabel, CursorShape,
     DiagnosticEntryRef, DiffOptions, EditPredictionsMode, EditPreview, HighlightedText, IndentKind,
-    IndentSize, Language, OffsetRangeExt, OutlineItem, Point, Runnable, RunnableRange, Selection,
-    SelectionGoal, TextObject, TransactionId, TreeSitterOptions, WordsQuery,
+    IndentSize, Language, LanguageRegistry, OffsetRangeExt, OutlineItem, Point, Runnable,
+    RunnableRange, Selection, SelectionGoal, TextObject, TransactionId, TreeSitterOptions,
+    WordsQuery,
     language_settings::{
         self, LspInsertMode, RewrapBehavior, WordsCompletionMode, all_language_settings,
         language_settings,
@@ -371,6 +372,7 @@ pub trait DiagnosticRenderer {
         buffer_id: BufferId,
         snapshot: EditorSnapshot,
         editor: WeakEntity<Editor>,
+        language_registry: Option<Arc<LanguageRegistry>>,
         cx: &mut App,
     ) -> Vec<BlockProperties<Anchor>>;
 
@@ -379,6 +381,7 @@ pub trait DiagnosticRenderer {
         diagnostic_group: Vec<DiagnosticEntryRef<'_, Point>>,
         range: Range<Point>,
         buffer_id: BufferId,
+        language_registry: Option<Arc<LanguageRegistry>>,
         cx: &mut App,
     ) -> Option<Entity<markdown::Markdown>>;
 
@@ -17947,8 +17950,18 @@ impl Editor {
             .diagnostic_group(buffer_id, diagnostic.diagnostic.group_id)
             .collect::<Vec<_>>();
 
-        let blocks =
-            renderer.render_group(diagnostic_group, buffer_id, snapshot, cx.weak_entity(), cx);
+        let language_registry = self
+            .project()
+            .map(|project| project.read(cx).languages().clone());
+
+        let blocks = renderer.render_group(
+            diagnostic_group,
+            buffer_id,
+            snapshot,
+            cx.weak_entity(),
+            language_registry,
+            cx,
+        );
 
         let blocks = self.display_map.update(cx, |display_map, cx| {
             display_map.insert_blocks(blocks, cx).into_iter().collect()

crates/editor/src/hover_popover.rs

@@ -341,7 +341,13 @@ fn show_hover(
                     renderer
                         .as_ref()
                         .and_then(|renderer| {
-                            renderer.render_hover(group, point_range, buffer_id, cx)
+                            renderer.render_hover(
+                                group,
+                                point_range,
+                                buffer_id,
+                                language_registry.clone(),
+                                cx,
+                            )
                         })
                         .context("no rendered diagnostic")
                 })??;
@@ -986,6 +992,11 @@ impl DiagnosticPopover {
                                     self.markdown.clone(),
                                     diagnostics_markdown_style(window, cx),
                                 )
+                                .code_block_renderer(markdown::CodeBlockRenderer::Default {
+                                    copy_button: false,
+                                    copy_button_on_hover: false,
+                                    border: false,
+                                })
                                 .on_url_click(
                                     move |link, window, cx| {
                                         if let Some(renderer) = GlobalDiagnosticRenderer::global(cx)