refactor: move all utility files to /common

src/common/lru-cache.ts

@@ -0,0 +1,31 @@
+export class LRUCache<K, V> {
+    private capacity: number;
+    private cache: Map<K, V>;
+
+    constructor(capacity: number) {
+        this.capacity = capacity;
+        this.cache = new Map<K, V>();
+    }
+
+    public get(key: K): V | undefined {
+        const value = this.cache.get(key);
+        if (value !== undefined) {
+            // Move the accessed key to the end to mark it as most recently used
+            this.cache.delete(key);
+            this.cache.set(key, value);
+        }
+        return value;
+    }
+
+    public put(key: K, value: V): void {
+        if (this.cache.has(key)) {
+            // If the key already exists, move it to the end to mark it as most recently used
+            this.cache.delete(key);
+        } else if (this.cache.size >= this.capacity) {
+            // If the cache is full, remove the least recently used key (the first one in the map)
+            const firstKey = this.cache.keys().next().value;
+            this.cache.delete(firstKey);
+        }
+        this.cache.set(key, value);
+    }
+}