Set up and manage the Sentry development environment using devenv. Handles fresh setup, updating existing environments, starting dev services, resetting the database, per-worktree environment setup (each worktree needs its own devenv sync/.venv), and troubleshooting. Use when asked to "set up sentry", "setup dev environment", "get sentry running", "start dev server", "devenv setup", "devservices not working", "sentry won't start", "reset the database", "new worktree venv/devenv setup", or any development environment issue.