Remove undocumented filtering from codegen, filter at blueprint creation

[razor-x]

Summary

This PR refactors the undocumented content filtering logic by moving it upstream to the blueprint creation step, rather than filtering throughout the codegen code. This simplifies the codegen by removing scattered isUndocumented checks and documentedProperties filtering calls.

Key Changes

• Removed documentedProperties helper function that filtered out undocumented properties - this filtering now happens at blueprint creation time
• Simplified resource model generation by removing isUndocumented checks for resources, events, and action attempts
• Simplified route generation by removing isUndocumented checks for routes and endpoints, and removing parameter filtering
• Updated blueprint initialization in smith.ts to use createBlueprint with omitUndocumented: true option, ensuring the blueprint only contains public API elements before codegen processes it

Implementation Details

• The createBlueprint function from @seamapi/blueprint is now called with omitUndocumented: true, which pre-filters all undocumented resources, endpoints, parameters, and properties
• This eliminates the need for defensive filtering throughout the codegen pipeline
• The codegen now operates on a "clean" blueprint that only contains documented elements, making the code simpler and more maintainable
• Changed from using the blueprint plugin to directly passing the blueprint via metadata

https://claude.ai/code/session_01BrQiAv7j9XMWD12S9ax9Bt