fix: retain select last token InfiniOps adapter

[voltjia]

Summary

• declare add and index_select as the InfiniOps dependencies of the composed select_last_token_hidden adapter
• retain that adapter when both aligned operators are selected through ops.json

Impact

Without an explicit dependency mapping, adapter filtering treats select_last_token_hidden as a direct InfiniOps operator. Since the aligned implementation is composed from add and index_select, the filter removes it and InfiniCore falls back to the legacy InfiniOp implementation even when both required InfiniOps operators are available.

This change only corrects source selection. It does not modify the adapter implementation, operator interfaces, or submodules.

Validation

• git diff --check
• validated from InfiniRT 6b256e0ab085, InfiniOps c8e15ebe9da4, InfiniCore 847c4c04fe18 plus this change, and InfiniLM 80bb09ecebc9
• built and installed InfiniRT and InfiniOps independently, then configured InfiniCore as an installed-package consumer on NVIDIA and MetaX
• ran Qwen3-0.6B paged-attention inference with greedy decoding on both platforms
• NVIDIA temporary route instrumentation reported only SELECT_ROUTE=infiniops for select_last_token_hidden
• MetaX GDB route counts reported select_infiniops=1, select_infiniop=0, and random_infiniop=0; aligned Argmax and linked flash-attention providers were exercised