Refactor caching and memory management components

- Updated the caching logic to utilize a predictive cache warmer, enhancing content prefetching based on access patterns.
- Replaced the legacy warming system with a more efficient predictive approach, allowing for better performance and resource management.
- Refactored memory management to integrate dynamic cache size adjustments based on system memory usage, improving overall efficiency.
- Simplified the VFS interface and improved concurrency handling with sharded locks for better performance in multi-threaded environments.
- Enhanced tests to validate the new caching and memory management behaviors, ensuring reliability and performance improvements.

vfs/locks/sharding.go

@@ -0,0 +1,28 @@
+package locks
+
+import (
+	"sync"
+)
+
+// Number of lock shards for reducing contention
+const NumLockShards = 32
+
+// GetShardIndex returns the shard index for a given key using FNV-1a hash
+func GetShardIndex(key string) int {
+	// Use FNV-1a hash for good distribution
+	var h uint32 = 2166136261 // FNV offset basis
+	for i := 0; i < len(key); i++ {
+		h ^= uint32(key[i])
+		h *= 16777619 // FNV prime
+	}
+	return int(h % NumLockShards)
+}
+
+// GetKeyLock returns a lock for the given key using sharding
+func GetKeyLock(keyLocks []sync.Map, key string) *sync.RWMutex {
+	shardIndex := GetShardIndex(key)
+	shard := &keyLocks[shardIndex]
+
+	keyLock, _ := shard.LoadOrStore(key, &sync.RWMutex{})
+	return keyLock.(*sync.RWMutex)
+}