Provide wasm extensions with APIs needed for using pre-installed LSP binaries (#9085)

In this PR, we've added two new methods that LSP extensions can call:
* `shell_env()`, for retrieving the environment variables set in the
user's default shell in the worktree
* `which(command)`, for looking up paths to an executable (accounting
for the user's shell env in the worktree)

To test this out, we moved the `uiua` language support into an
extension. We went ahead and removed the built-in support, since this
language is extremely obscure. Sorry @mikayla-maki. To continue coding
in Uiua in Zed, for now you can `Add Dev Extension` from the extensions
pane, and select the `extensions/uiua` directory in the Zed repo. Very
soon, we'll support publishing these extensions so that you'll be able
to just install it normally.

Release Notes:

- N/A

---------

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

crates/languages/src/lib.rs

@@ -39,7 +39,6 @@ mod tailwind;
 mod terraform;
 mod toml;
 mod typescript;
-mod uiua;
 mod vue;
 mod yaml;
 mod zig;
@@ -114,7 +113,6 @@ pub fn init(
         ("toml", tree_sitter_toml::language()),
         ("tsx", tree_sitter_typescript::language_tsx()),
         ("typescript", tree_sitter_typescript::language_typescript()),
-        ("uiua", tree_sitter_uiua::language()),
         ("vue", tree_sitter_vue::language()),
         ("yaml", tree_sitter_yaml::language()),
         ("zig", tree_sitter_zig::language()),
@@ -344,7 +342,6 @@ pub fn init(
         "vue",
         vec![Arc::new(vue::VueLspAdapter::new(node_runtime.clone()))]
     );
-    language!("uiua", vec![Arc::new(uiua::UiuaLanguageServer {})]);
     language!("proto");
     language!("terraform", vec![Arc::new(terraform::TerraformLspAdapter)]);
     language!(