Add linting to the mobile app and include core and api-client
packages in the root lint, typecheck, and test scripts. Ignore
node_modules in all subdirectories and clean up stale test results.
Update lint and typecheck scripts for all packages
Add ESLint configuration for mobile app and shared packages.
Rename mobile jest config to .cjs and enable ESM. Include
packages/core and packages/api-client in monorepo lint,
typecheck, and test scripts.
