Bail and signal error when the cwd of a resolved task doesn't exist (#32777)

Closes #32688

Release Notes:

- Fixed tasks (including build tasks for debug configurations) silently
using `/` as a working directory when the specified `cwd` didn't exist.

crates/terminal_view/src/terminal_panel.rs

@@ -1461,10 +1461,27 @@ impl workspace::TerminalProvider for TerminalProvider {
         &self,
         task: SpawnInTerminal,
         window: &mut Window,
-        cx: &mut App,
+        cx: &mut Context<Workspace>,
     ) -> Task<Option<Result<ExitStatus>>> {
         let terminal_panel = self.0.clone();
+        let workspace = cx.weak_entity();
         window.spawn(cx, async move |cx| {
+            if let Some(cwd) = task.cwd.as_deref() {
+                let result = match smol::fs::metadata(cwd).await {
+                    Ok(metadata) if metadata.is_dir() => Ok(()),
+                    Ok(_) => Err(anyhow!("cwd for resolved task is not a directory: {cwd:?}")),
+                    Err(e) => Err(e).context(format!("reading cwd of resolved task: {cwd:?}")),
+                };
+                if let Err(e) = result {
+                    workspace
+                        .update(cx, |workspace, cx| {
+                            workspace.show_error(&e, cx);
+                        })
+                        .ok();
+                    return None;
+                }
+            }
+
             let terminal = terminal_panel
                 .update_in(cx, |terminal_panel, window, cx| {
                     terminal_panel.spawn_task(&task, window, cx)