[rit3sh-x]

Summary

Reduces IAVL cache memory usage and prevents pruning from polluting the node cache.

• Value size limit: Adds CacheValueSizeLimitOption to skip caching leaves and fast nodes with values larger than the configured limit. Oversized fast nodes are also removed from the cache.
• Fast node cache size: Adds FastNodeCacheSizeOption to configure the fast-node cache capacity. Defaults remain unchanged (100,000 entries).
• Pruner cache hygiene: Evicts deleted nodes from the cache, avoids refreshing LRU order or caching misses during pruning, and evicts entries before updating cached node nonces.

Testing

• make legacydump && go test ./... passes.
• Targeted race tests for pruning, caches, fast nodes, legacy, and nodedb pass.
• Existing iterator concurrency race reports are unchanged from master.

[greptile-apps]

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