Support bracket colorization (rainbow brackets) (#43172)

Deals with https://github.com/zed-industries/zed/issues/5259

Highlights brackets with different colors based on their depth.
Uses existing tree-sitter queries from brackets.scm to find brackets,
uses theme's accents to color them.


https://github.com/user-attachments/assets/cc5f3aba-22fa-446d-9af7-ba6e772029da

1. Adds `colorize_brackets` language setting that allows, per language
or globally for all languages, to configure whether Zed should color the
brackets for a particular language.

Disabled for all languages by default.

2. Any given language can opt-out a certain bracket pair by amending the
brackets.scm like `("\"" @open "\"" @close) ` -> `(("\"" @open "\""
@close) (#set! rainbow.exclude))`

3. Brackets are using colors from theme accents, which can be overridden
as

```jsonc
"theme_overrides": {
  "One Dark": {
    "accents": ["#ff69b4", "#7fff00", "#ff1493", "#00ffff", "#ff8c00", "#9400d3"]
  }
},
```

Release Notes:

- Added bracket colorization (rainbow brackets) support. Use
`colorize_brackets` language setting to enable.

---------

Co-authored-by: MrSubidubi <dev@bahn.sh>
Co-authored-by: Lukas Wirth <lukas@zed.dev>
Co-authored-by: MrSubidubi <finn@zed.dev>
Co-authored-by: Lukas Wirth <me@lukaswirth.dev>
Co-authored-by: Smit Barmase <heysmitbarmase@gmail.com>

crates/language/src/buffer_tests.rs

@@ -1111,9 +1111,10 @@ fn test_text_objects(cx: &mut App) {
 
 #[gpui::test]
 fn test_enclosing_bracket_ranges(cx: &mut App) {
-    let mut assert = |selection_text, range_markers| {
+    #[track_caller]
+    fn assert(selection_text: &'static str, range_markers: Vec<&'static str>, cx: &mut App) {
         assert_bracket_pairs(selection_text, range_markers, rust_lang(), cx)
-    };
+    }
 
     assert(
         indoc! {"
@@ -1130,6 +1131,7 @@ fn test_enclosing_bracket_ranges(cx: &mut App) {
                 }
             «}»
             let foo = 1;"}],
+        cx,
     );
 
     assert(
@@ -1156,6 +1158,7 @@ fn test_enclosing_bracket_ranges(cx: &mut App) {
                 }
                 let foo = 1;"},
         ],
+        cx,
     );
 
     assert(
@@ -1182,6 +1185,7 @@ fn test_enclosing_bracket_ranges(cx: &mut App) {
                 }
                 let foo = 1;"},
         ],
+        cx,
     );
 
     assert(
@@ -1199,6 +1203,7 @@ fn test_enclosing_bracket_ranges(cx: &mut App) {
                 }
             «}»
             let foo = 1;"}],
+        cx,
     );
 
     assert(
@@ -1209,7 +1214,8 @@ fn test_enclosing_bracket_ranges(cx: &mut App) {
                 }
             }
             let fˇoo = 1;"},
-        vec![],
+        Vec::new(),
+        cx,
     );
 
     // Regression test: avoid crash when querying at the end of the buffer.
@@ -1221,7 +1227,8 @@ fn test_enclosing_bracket_ranges(cx: &mut App) {
                 }
             }
             let foo = 1;ˇ"},
-        vec![],
+        Vec::new(),
+        cx,
     );
 }