var-picker not update when edges change in node panel

[HiChen404]

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Dify version

0.8.0

Cloud or Self Hosted

Cloud

Steps to reproduce

When focusing on a node and changing the connection, the variables in the var-picker will not be updated to the latest.

https://github.com/user-attachments/assets/d51d62e5-0c65-4aee-822d-b91d6b268a56

✔️ Expected Behavior

var list updated to the latest when connected edges change.

❌ Actual Behavior

Refresh only when switching node panel.