Fix debugger on Windows (#35180)

Closes #33429

Release Notes:

- N/A

crates/project/src/debugger/dap_store.rs

@@ -920,12 +920,22 @@ impl dap::adapters::DapDelegate for DapAdapterDelegate {
         self.console.unbounded_send(msg).ok();
     }
 
+    #[cfg(not(target_os = "windows"))]
     async fn which(&self, command: &OsStr) -> Option<PathBuf> {
         let worktree_abs_path = self.worktree.abs_path();
         let shell_path = self.shell_env().await.get("PATH").cloned();
         which::which_in(command, shell_path.as_ref(), worktree_abs_path).ok()
     }
 
+    #[cfg(target_os = "windows")]
+    async fn which(&self, command: &OsStr) -> Option<PathBuf> {
+        // On Windows, `PATH` is handled differently from Unix. Windows generally expects users to modify the `PATH` themselves,
+        // and every program loads it directly from the system at startup.
+        // There's also no concept of a default shell on Windows, and you can't really retrieve one, so trying to get shell environment variables
+        // from a specific directory doesn’t make sense on Windows.
+        which::which(command).ok()
+    }
+
     async fn shell_env(&self) -> HashMap<String, String> {
         let task = self.load_shell_env_task.clone();
         task.await.unwrap_or_default()