Support running a command after creating new folder

Feature Request: Run Command After Creating Folder

Currently, try creates new directories but doesn't support running initialization commands.

Proposed Feature: Add a --run flag or similar option to execute a command after creating and entering the new directory.

Example Usage:

try . --run "npx motia@latest create"

This would:

1. Create a dated directory (e.g., 2025-01-06-my-project)
2. Change into the directory
3. Execute the specified command

Use Cases:

• Initialize projects with framework-specific commands
• Run setup scripts after creating experiment directories
• Automate common post-creation tasks

This would be particularly useful for quickly starting new experiments with specific tooling.

Start at the try command's option parsing and directory-creation flow, since the issue names no files or tests. Confirm how the command enters the new directory, then verify that the --run example executes afterward while existing directory creation still works.