Add separate JSONC language (#12655)

Resolves https://github.com/zed-industries/extensions/issues/860 and
https://github.com/zed-industries/zed/issues/10921, also
https://github.com/biomejs/biome-zed/issues/11.

### Problem:
When opening .json files, zed allows comments by default in the JSON
language, which can cause some problems.
For example, language-servers also get "json" as the language, which may
show errors for those comments.

<img width="935" alt="image"
src="https://github.com/zed-industries/zed/assets/10381895/fed3d83d-abc0-44b5-9982-eb249bb04c3b">

### Solution:

This PR adds a JSONC language. 

<img width="816" alt="image"
src="https://github.com/zed-industries/zed/assets/10381895/8b40e671-d4f0-4e8d-80cb-82ee7c0ec490">

This allows for more specific configuration for language servers. 
Also any json file can be set explicitly to be JSONC using the
file_types setting:

```jsonc
{
  "file_types": {
    // set all .json files to be seen as JSONC
    "JSONC": ["*.json"]
  }
}
```


Release Notes:

- N/A

crates/language/src/language_settings.rs

@@ -662,6 +662,17 @@ impl settings::Settings for AllLanguageSettings {
             .ok_or_else(Self::missing_default)?;
 
         let mut file_types: HashMap<Arc<str>, GlobSet> = HashMap::default();
+
+        for (language, suffixes) in &default_value.file_types {
+            let mut builder = GlobSetBuilder::new();
+
+            for suffix in suffixes {
+                builder.add(Glob::new(suffix)?);
+            }
+
+            file_types.insert(language.clone(), builder.build()?);
+        }
+
         for user_settings in sources.customizations() {
             if let Some(copilot) = user_settings.features.as_ref().and_then(|f| f.copilot) {
                 copilot_enabled = Some(copilot);
@@ -701,6 +712,15 @@ impl settings::Settings for AllLanguageSettings {
             for (language, suffixes) in &user_settings.file_types {
                 let mut builder = GlobSetBuilder::new();
 
+                let default_value = default_value.file_types.get(&language.clone());
+
+                // Merge the default value with the user's value.
+                if let Some(suffixes) = default_value {
+                    for suffix in suffixes {
+                        builder.add(Glob::new(suffix)?);
+                    }
+                }
+
                 for suffix in suffixes {
                     builder.add(Glob::new(suffix)?);
                 }