Refactor: Bring RWGPS library inline

[TobyHFerguson]

Recommendation: Bring the code into this workspace as inline modules following your existing architecture pattern.

Why Inline Makes Sense
Your situation:

✅ Library only used by this one project
✅ Library needs updating anyway
✅ You already have strong testing/architecture patterns here
✅ GAS deployment is simpler with fewer dependencies
Architecture approach:

Benefits:

✅ Single deployment: One npm run prod:push updates everything
✅ Easier debugging: All code in one place
✅ Same quality standards: 100% coverage, TypeScript types
✅ Follows your pattern: Core (testable) + Adapter (GAS APIs)
✅ Simpler refactoring: No cross-project coordination
You'd keep:

Clear API boundary (RWGPSCore exports public interface)
Full test coverage (Jest tests for all logic)
Type safety (TypeScript definitions)
You'd lose:

Separate versioning (but you're the only user)
Reusability (but it's not being reused)
Migration path:

Copy library code into src/RWGPSCore.js (pure logic)
Create src/RWGPS.js adapter (UrlFetchApp calls)
Write comprehensive tests (100% coverage)
Update your current code to use new modules
Delete external library dependency