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/db/src/db.rs

@@ -20,7 +20,7 @@ use sqlez_macros::sql;
 use std::future::Future;
 use std::path::{Path, PathBuf};
 use std::sync::atomic::{AtomicBool, Ordering};
-use util::{async_maybe, ResultExt};
+use util::{maybe, ResultExt};
 
 const CONNECTION_INITIALIZE_QUERY: &str = sql!(
     PRAGMA foreign_keys=TRUE;
@@ -57,7 +57,7 @@ pub async fn open_db<M: Migrator + 'static>(
     let release_channel_name = release_channel.dev_name();
     let main_db_dir = db_dir.join(Path::new(&format!("0-{}", release_channel_name)));
 
-    let connection = async_maybe!({
+    let connection = maybe!(async {
         smol::fs::create_dir_all(&main_db_dir)
             .await
             .context("Could not create db directory")