Fix issues with extension API that come up when moving Svelte into an extension (#9611)

We're doing it. Svelte support is moving into an extension. This PR
fixes some issues that came up along the way.

Notes

* extensions need to be able to retrieve the path the `node` binary
installed by Zed
* previously we were silently swallowing any errors that occurred while
loading a grammar
* npm commands ran by extensions weren't run in the right directory
* Tree-sitter's WASM stdlib didn't support a C function (`strncmp`)
needed by the Svelte parser's external scanner
* the way that LSP installation status was reported was unnecessarily
complex

Release Notes:

- Removed built-in support for the Svelte and Gleam languages, because
full support for those languages is now available via extensions. These
extensions will be suggested for download when you open a `.svelte` or
`.gleam` file.

---------

Co-authored-by: Marshall <marshall@zed.dev>

crates/languages/src/lib.rs

@@ -22,7 +22,6 @@ mod dockerfile;
 mod elixir;
 mod elm;
 mod erlang;
-mod gleam;
 mod go;
 mod haskell;
 mod html;
@@ -36,7 +35,6 @@ mod purescript;
 mod python;
 mod ruby;
 mod rust;
-mod svelte;
 mod tailwind;
 mod terraform;
 mod toml;
@@ -83,7 +81,6 @@ pub fn init(
             tree_sitter_embedded_template::language(),
         ),
         ("erlang", tree_sitter_erlang::language()),
-        ("gleam", tree_sitter_gleam::language()),
         ("glsl", tree_sitter_glsl::language()),
         ("go", tree_sitter_go::language()),
         ("gomod", tree_sitter_gomod::language()),
@@ -113,7 +110,6 @@ pub fn init(
         ("ruby", tree_sitter_ruby::language()),
         ("rust", tree_sitter_rust::language()),
         ("scheme", tree_sitter_scheme::language()),
-        ("svelte", tree_sitter_svelte::language()),
         ("toml", tree_sitter_toml::language()),
         ("tsx", tree_sitter_typescript::language_tsx()),
         ("typescript", tree_sitter_typescript::language_typescript()),
@@ -237,8 +233,6 @@ pub fn init(
         }
     }
     language!("erlang", vec![Arc::new(erlang::ErlangLspAdapter)]);
-
-    language!("gleam", vec![Arc::new(gleam::GleamLspAdapter)]);
     language!("go", vec![Arc::new(go::GoLspAdapter)]);
     language!("gomod");
     language!("gowork");
@@ -346,13 +340,6 @@ pub fn init(
         "yaml",
         vec![Arc::new(yaml::YamlLspAdapter::new(node_runtime.clone()))]
     );
-    language!(
-        "svelte",
-        vec![
-            Arc::new(svelte::SvelteLspAdapter::new(node_runtime.clone())),
-            Arc::new(tailwind::TailwindLspAdapter::new(node_runtime.clone())),
-        ]
-    );
     language!(
         "php",
         vec![
@@ -393,6 +380,11 @@ pub fn init(
         ))]
     );
     language!("dart", vec![Arc::new(dart::DartLanguageServer {})]);
+
+    languages.register_secondary_lsp_adapter(
+        "Svelte".into(),
+        Arc::new(tailwind::TailwindLspAdapter::new(node_runtime.clone())),
+    );
 }
 
 #[cfg(any(test, feature = "test-support"))]