【bug】prompt is too long

[zengxiangqi1031]

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Dify version

0.6.12-fix1

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

when i use claude3.5-sonnet(support 200k) to tag a photo about 1.5MB as agent ， dify said prompt tokens are 1500000+ tokens much bigger than 200k; when i debug api module, i found than prompt tokens are caculated by the photo‘s bytes

✔️ Expected Behavior

prompt tokens should be calculated correctly.

❌ Actual Behavior

No response