[cpplings] Add STL containers and algorithms exercises

[XueSongTap]

Enhancement This sub-issue will add Standard Template Library (STL) usage exercises to the cpplings directory.

The exercises will cover:

• Common containers (vector, list, map, set, etc.) and their operations
• Iterator usage patterns
• Algorithm library (std::algorithm) function examples
• Functional programming style with STL

These exercises will help contributors better leverage the C++ STL library in the MiniOB project.

Parent issue: #508 (add more cpplings case)

[nautaa]

do you want to pick up this issue and #525 ?

[XueSongTap]

@nautaa sure, I will do this and #525