⚡ Bolt: Optimize O(N^2) list lookups in case retrieval

[mapleleaflatte03]

💡 What: Replaced linear array lookups with O(1) Set lookups in blocking_commitment_ids and blocked_peer_host_ids in kernel/kernel/cases.py. Also added .jules/bolt.md to document the learning.

🎯 Why: During case-retrieval inside frequent routines (like queue dispatch), tracking visited items via a List and applying the not in operator triggers O(N) operations inside a loop, resulting in O(N^2) time complexity. Using Python sets dramatically drops the overhead to O(1) checks.

📊 Impact: Reduces computational overhead by transforming O(N^2) algorithms to linear O(N) traversals on the case lookup operations, eliminating an exponential scaling factor that could choke the message handoff execution loops as scale increases.

🔬 Measurement: Verify tests run completely successfully. Profiling any multi-host queue simulations will show reduced CPU time on dictionary lookups versus array containment.

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PR created automatically by Jules for task 7014413194624005492 started by @mapleleaflatte03

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