Implement smart cache size management with LRU eviction

[RUKAYAT-CODER]

Background

Cache can grow unbounded consuming all storage. Implement LRU (Least Recently Used) eviction policy with configurable max size. When cache approaches limit, evict oldest/least-used items.

Description

Implement LRU cache eviction to prevent unbounded cache growth.

Current Behavior

Cache grows indefinitely until storage full

Expected Behavior

LRU eviction maintains max cache size

Impact

💾 Bounded memory usage
🛡️ Prevent storage exhaustion
📊 Predictable cache performance

Acceptance Criteria

• Implement LRU eviction policy
• Set max cache size (e.g., 100MB)
• Evict least recently used items when limit reached
• Test cache behavior at limit
• Verify no data loss during eviction
• Monitor cache hit rate impact
• Document cache management

Implementation Hints

Use LRU data structure (Map with ordering). Track access times.

Performance Metrics

Before:

• storageUsage: Grows until 100% (OOM)

After (Target):

• storageUsage: Capped at 100 MB with LRU

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