fix(workflow): validate node compatibility when importing dsl between chatflows and workflows

[yangzheli]

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Summary

fix #24883

• use js-yaml to parse dsl content, and validate node compatibility when importing dsl between chatflows and workflows in the frontend

Screenshots

Before

2025-11-09.11.20.42.mov

After

• import workflow without end node

2025-11-09.11.17.48.mov

• import workflow with end node

2025-11-09.11.18.36.mov

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

[gemini-code-assist]

Code Review

This pull request introduces frontend validation to prevent importing incompatible DSL files between chatflows and workflows, which is a great improvement for user experience. The implementation correctly uses js-yaml to parse the DSL and checks for invalid node types based on the application mode. The logic is sound and directly addresses the issue. I have one suggestion to refactor the new validation function for better readability and maintainability.