feat(fmt): support CSS, SCSS, Sass and Less (#24870)

This PR integrates [Malva](https://github.com/g-plane/malva) into `deno
fmt`, which introduces the ability to format CSS, SCSS, Sass and Less
files.

On Linux x64 6.10, this PR increases about 800KiB:

```                                                                                                                                                                      
❯ wc -c target/release/deno
125168728 target/release/deno

❯ wc -c target/release/deno
124349456 target/release/deno
```

1 files changed, 6 insertions, 1 deletions

diff --git a/cli/args/mod.rs b/cli/args/mod.rs
index bd49c0c15..afad0528c 100644
--- a/cli/args/mod.rs
+++ b/cli/args/mod.rs
@@ -281,6 +281,7 @@ impl BenchOptions {
 
 #[derive(Clone, Debug, Default, PartialEq, Eq, Hash)]
 pub struct UnstableFmtOptions {
+  pub css: bool,
   pub yaml: bool,
 }
 
@@ -314,6 +315,7 @@ impl FmtOptions {
     Self {
       options: resolve_fmt_options(fmt_flags, fmt_config.options),
       unstable: UnstableFmtOptions {
+        css: unstable.css || fmt_flags.unstable_css,
         yaml: unstable.yaml || fmt_flags.unstable_yaml,
       },
       files: fmt_config.files,
@@ -1330,8 +1332,10 @@ impl CliOptions {
   }
 
   pub fn resolve_config_unstable_fmt_options(&self) -> UnstableFmtOptions {
+    let workspace = self.workspace();
     UnstableFmtOptions {
-      yaml: self.workspace().has_unstable("fmt-yaml"),
+      css: workspace.has_unstable("fmt-css"),
+      yaml: workspace.has_unstable("fmt-yaml"),
     }
   }
 
@@ -1664,6 +1668,7 @@ impl CliOptions {
         "sloppy-imports",
         "byonm",
         "bare-node-builtins",
+        "fmt-css",
         "fmt-yaml",
       ]);
       // add more unstable flags to the same vector holding granular flags