Add a JS/TS debug locator (#31769)

With this, a semi-working debug session is possible from the JS/TS
gutter tasks:


https://github.com/user-attachments/assets/8db6ed29-b44a-4314-ae8b-a8213291bffc

For now, available in debug builds only as a base to improve on later on
the DAP front.

Release Notes:

- N/A

---------

Co-authored-by: Piotr Osiewicz <peterosiewicz@gmail.com>

crates/dap/src/adapters.rs

@@ -298,6 +298,7 @@ pub async fn download_adapter_from_github(
         response.status().to_string()
     );
 
+    delegate.output_to_console("Download complete".to_owned());
     match file_type {
         DownloadedFileType::GzipTar => {
             let decompressed_bytes = GzipDecoder::new(BufReader::new(response.body_mut()));

crates/dap/src/transport.rs

@@ -434,7 +434,7 @@ impl TransportDelegate {
                 .with_context(|| "reading a message from server")?
                 == 0
             {
-                anyhow::bail!("debugger reader stream closed");
+                anyhow::bail!("debugger reader stream closed, last string output: '{buffer}'");
             };
 
             if buffer == "\r\n" {