[Usage]: AscendDirectTransport fails with “ctx js NULL” on CANN 9.1.0 and Mooncake 0.3.12

### Describe your usage question

Environment
•Hardware: Ascend 910B4
•HDK: 25.5.1
•CANN Docker Image: cann:9.1.0-910b-openeuler24.03-py3.12-devel
•Mooncake Version: 0.3.12.post1 (installed via pip install mooncake-transfer-engine-npu)

Questions
It seems the mooncake_store process did not properly initialize the ACL device context(aclrtSetDevice/aclrtCreateContext) or select the correct device before allocating the local segment under CANN 9.1.0.
Could you please confirm if this version combination is officially supported, or if there is any workaround/fix required? Thanks!

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