Add default language server for CSS (#2025)

book/src/generated/lang-support.md

@@ -6,7 +6,7 @@
 | cmake | ✓ | ✓ | ✓ | `cmake-language-server` |
 | comment | ✓ |  |  |  |
 | cpp | ✓ | ✓ | ✓ | `clangd` |
-| css | ✓ |  |  |  |
+| css | ✓ |  |  | `vscode-css-language-server` |
 | dart | ✓ |  | ✓ | `dart` |
 | dockerfile | ✓ |  |  | `docker-langserver` |
 | elixir | ✓ |  |  | `elixir-ls` |

languages.toml

@@ -339,6 +339,7 @@ scope = "source.css"
 injection-regex = "css"
 file-types = ["css", "scss"]
 roots = []
+language-server = { command = "vscode-css-language-server", args = ["--stdio"] }
 indent = { tab-width = 2, unit = "  " }
 
 [[grammar]]