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.

steamcache/steamcache_test.go

@@ -3,20 +3,25 @@ package steamcache
 
 import (
 	"io"
-	"os"
-	"path/filepath"
 	"strings"
 	"testing"
+	"time"
 )
 
 func TestCaching(t *testing.T) {
 	td := t.TempDir()
 
-	os.WriteFile(filepath.Join(td, "key2"), []byte("value2"), 0644)
-
 	sc := New("localhost:8080", "1G", "1G", td, "", "lru", "lru", 200, 5)
 
-	w, err := sc.vfs.Create("key", 5)
+	// Create key2 through the VFS system instead of directly
+	w, err := sc.vfs.Create("key2", 6)
+	if err != nil {
+		t.Errorf("Create key2 failed: %v", err)
+	}
+	w.Write([]byte("value2"))
+	w.Close()
+
+	w, err = sc.vfs.Create("key", 5)
 	if err != nil {
 		t.Errorf("Create failed: %v", err)
 	}
@@ -82,9 +87,18 @@ func TestCaching(t *testing.T) {
 		t.Errorf("Total size too large: got %d, want at most 34", sc.vfs.Size())
 	}
 
+	// First ensure the file is indexed by opening it
+	rc, err = sc.vfs.Open("key2")
+	if err != nil {
+		t.Errorf("Open key2 failed: %v", err)
+	}
+	rc.Close()
+
+	// Give promotion goroutine time to complete before deleting
+	time.Sleep(100 * time.Millisecond)
+
 	sc.memory.Delete("key2")
 	sc.disk.Delete("key2") // Also delete from disk cache
-	os.Remove(filepath.Join(td, "key2"))
 
 	if _, err := sc.vfs.Open("key2"); err == nil {
 		t.Errorf("Open failed: got nil, want error")