[CLEAN] Synthetic Benchmark PR #28525 - feat(api): automatically NODE_TYPE_CLASSES_MAPPING generation from node class definitions

[tomerqodo]

Benchmark PR langgenius#28525

Type: Clean (correct implementation)

Original PR Title: feat(api): automatically NODE_TYPE_CLASSES_MAPPING generation from node class definitions
Original PR Description: > [!IMPORTANT]

1. Make sure you have read our contribution guidelines
2. Ensure there is an associated issue and you have been assigned to it
3. Use the correct syntax to link this PR: Fixes #<issue number>.

Summary

fix langgenius#28524 NODE_TYPE_CLASSES_MAPPING auto generate

Screenshots

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Checklist

• This change requires a documentation update, included: Dify Document
• I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.
• I ran dev/reformat(backend) and cd web && npx lint-staged(frontend) to appease the lint gods

Original PR URL: langgenius#28525