Omit tsdk_path from the servers' options if it does not exist (#23525)

Part of https://github.com/zed-industries/zed/issues/22606

Before, `tsdk_path` for vtsls and typescript-language-server
unconditionally set a `tsdk`/`tsserver` property for the corresponding
language server, even if there were no such directory at all.
Instead, make the corresponding code to omit such property if it was not
found on the FS.

Release Notes:

- Fixed "The path /.../tsserver.js doesn't point to a valid tsserver
install. Falling back to bundled TypeScript version." pop-up appearing

crates/language_extension/Cargo.toml

@@ -17,6 +17,7 @@ async-trait.workspace = true
 collections.workspace = true
 extension.workspace = true
 futures.workspace = true
+fs.workspace = true
 gpui.workspace = true
 language.workspace = true
 lsp.workspace = true

crates/language_extension/src/extension_lsp_adapter.rs

@@ -8,6 +8,7 @@ use anyhow::{Context, Result};
 use async_trait::async_trait;
 use collections::HashMap;
 use extension::{Extension, ExtensionLanguageServerProxy, WorktreeDelegate};
+use fs::Fs;
 use futures::{Future, FutureExt};
 use gpui::AsyncAppContext;
 use language::{
@@ -224,6 +225,7 @@ impl LspAdapter for ExtensionLspAdapter {
 
     async fn initialization_options(
         self: Arc<Self>,
+        _: &dyn Fs,
         delegate: &Arc<dyn LspAdapterDelegate>,
     ) -> Result<Option<serde_json::Value>> {
         let delegate = Arc::new(WorktreeDelegateAdapter(delegate.clone())) as _;
@@ -246,6 +248,7 @@ impl LspAdapter for ExtensionLspAdapter {
 
     async fn workspace_configuration(
         self: Arc<Self>,
+        _: &dyn Fs,
         delegate: &Arc<dyn LspAdapterDelegate>,
         _: Arc<dyn LanguageToolchainStore>,
         _cx: &mut AsyncAppContext,