Terminal tool improvements (#29924)

WIP

- On macOS/Linux, run the command in bash instead of the user's shell
- Try to prevent the agent from running commands that expect interaction

Release Notes:

- Agent Beta: Switched to using `bash` (if available) instead of the
user's shell when calling the terminal tool.
- Agent Beta: Prevented the agent from hanging when trying to run
interactive commands.

---------

Co-authored-by: WeetHet <stas.ale66@gmail.com>

Cargo.lock

@@ -735,6 +735,7 @@ dependencies = [
  "language_model",
  "language_models",
  "linkme",
+ "log",
  "open",
  "paths",
  "portable-pty",
@@ -761,6 +762,7 @@ dependencies = [
  "unindent",
  "util",
  "web_search",
+ "which 6.0.3",
  "workspace",
  "workspace-hack",
  "zed_llm_client",