Bpp9000 mining algorithm

[cyber-pc]

This PR,

• Add not-yet-optimized (scalar reference) version of score_bpp9000 into the pipeline
• Add score field to mining solution message, mining solution transaction, and system solution
• Miner ranking now depends on best score, with tick number as tie-breaker and worst-miner eviction
• Score is now an error count (smaller is better); one shared random2 pool per epoch
• Select algorithm by a distinct nonce[0] byte value (merged into the AlgoType enum)
• Load and hash-verify the task file on the node; keep it resident and re-apply after each epoch transition
• Add the bpp9000 scorer unit tests and regenerate golden data via Qiner (pop-64, K=0)
• Remove dead code: oddNonce, BPP9000_COUNT_WASTE, unused score_reference.h