[CLEAN] Synthetic Benchmark PR #30412 - fix(web): enable JSON_OBJECT type support in console UI

[tomerqodo]

Benchmark PR langgenius#30412

Type: Clean (correct implementation)

Original PR Title: fix(web): enable JSON_OBJECT type support in console UI
Original PR Description: ## Summary

PR langgenius#29053 introduced JSON_OBJECT support for user inputs. It also introduced an optional JSONSchema validation for json object inputs. However, the JSON_OBJECT option is not enabled in chatflow / workflow orchestration page, leading to confusions.

This PR addresses the problem by removing relevant feature flags in frontend code. It also adjusts how the JSONSchema is edited: the original implementation fills the top level properties for the user, while the current implementation only ensures that the type field of JSONSchema is object if the is JSON Schema field is set.

Fix: langgenius#29519

Screenshots

Before	After

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#30412