Previously generators could generate code from inputs that didn't exist and get back the empty string. This silent failure was causing problems for diagnosing issues. This PR changes the behaviour so that an error is thrown.
This will break generators which rely on the previous behaviour. Several of our demo blocks needed editing to accomodate this change.
Resolves#7665
* refactor(generators): Migrate lua_generator.js to TypeScript
* refactor(generators): Migrate generators/lua/* to TypeScript
* fix(generators): Fix type errors in generator functions
* refactor(generators): Migrate generators/lua.js to TypeScript
* chore(generator): Format
* chore(generators): JSDoc and formatting tweaks for PR #7654
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Co-authored-by: Christopher Allen <cpcallen+git@google.com>