Fix e2e regressions in HF export mask handling for QNN path

[fangyangci]

Summary

• DistilBERT fill-mask/question-answering and BLIP image-to-text e2e regressions

Root causes

• SDPA attention mask dtype mismatch
• decoder kwargs path incompatibility
• BLIP decoder mask shape mismatch

Fixes

• export IO bool normalization for binary attention_mask
• robust transformers compat patching
• decoder_wrapper kwargs support
• BLIP 2D mask pass-through

Validation

• focused unit tests passed
• e2e passed: question-answering, fill-mask, image-to-text-fp16