feat: validate examples (#48)

* feat: add linting rules

* feat: update steel-sdk versions

* feat: add more rules

* fix: all linting errors

* feat: add ci

* fix: pin zod version for stagehand example

* fix: add no-env check

* fix: remove lockfile

* feat: inject secrets

* fix: run bugs

* feat: standardize error handling

* fix: add newline

* fix: correctly exit extension examples

* ci: add timeout

* feat: centralize error handling