Repository setup, pnpm, and validation workflow

Before coding or validating repository work, load the repo-setup skill before situation-specific skills, read applicable AGENTS.md and CONTRIBUTING.md, and inspect the latest relevant package.json and repository rules for scripts, package-manager versions, runtime requirements, and dependency configuration. For packages/cli, run declared scripts there or via pnpm --filter sentry run <script>, including required preprocessing and generation. Validate relevant tests and project-defined typecheck, lint, dependency, error-pattern, fragment, and repository checks; report failures precisely and rerun them directly when needed. In this pnpm/esbuild project, add packages only to devDependencies with pnpm add -D <package>; never use runtime dependencies, because esbuild bundles runtime code and check:deps enforces this policy.