debugger: Fix issues with launch.json handling (#32563)

After this PR we can run all the in-tree launch.json examples from [this
repo](https://github.com/microsoft/vscode-recipes).

Things done:

- Fill in default cwd at a lower level for all adapters
- Update launch.json parsing for DebugScenario changes
- Imitate how VS Code normalizes the `type` field for JS debug tasks
- Make version field optional
- Extend the variable replacer a bit

Release Notes:

- Debugger Beta: fixed issues preventing loading and running of debug
tasks from VS Code's launch.json.

---------

Co-authored-by: Anthony Eid <hello@anthonyeid.me>
Co-authored-by: Anthony <anthony@zed.dev>
Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>

crates/dap_adapters/src/php.rs

@@ -71,6 +71,12 @@ impl PhpDebugAdapter {
         let tcp_connection = task_definition.tcp_connection.clone().unwrap_or_default();
         let (host, port, timeout) = crate::configure_tcp_connection(tcp_connection).await?;
 
+        let mut configuration = task_definition.config.clone();
+        if let Some(obj) = configuration.as_object_mut() {
+            obj.entry("cwd")
+                .or_insert_with(|| delegate.worktree_root_path().to_string_lossy().into());
+        }
+
         Ok(DebugAdapterBinary {
             command: Some(
                 delegate
@@ -95,7 +101,7 @@ impl PhpDebugAdapter {
             cwd: Some(delegate.worktree_root_path().to_path_buf()),
             envs: HashMap::default(),
             request_args: StartDebuggingRequestArguments {
-                configuration: task_definition.config.clone(),
+                configuration,
                 request: <Self as DebugAdapter>::request_kind(self, &task_definition.config)?,
             },
         })