Add Missing Search Algorithms

✅ Array/Search Space-Based Algorithms:

 Exponential Search – Efficient for unbounded/sorted arrays

 Fibonacci Search – Similar to binary search but uses Fibonacci numbers

 Sentinel Search – Optimized linear search

✅ Graph/Tree-Based Search Algorithms:

 Breadth-First Search (BFS)

 Depth-First Search (DFS)

 Dijkstra’s Algorithm

 Greedy Best-First Search