[Snippets-C++] Added two snippets from #209

[majvax]

Description

• Added the two snippets from Added C++ vector manipulation snippets. #209.
• Moved filter and transform from array-manipulation to vector-manipulation, it make more sense since both std::vector and std::array exists.

Type of Change

• ✨ New snippet
• 🛠 Improvement to an existing snippet
• 🐞 Bug fix
• 📖 Documentation update
• 🔧 Other (please describe):

Checklist

• I have tested my code and verified it works as expected.
• My code follows the style and contribution guidelines of this project.
• Comments are added where necessary for clarity.
• Documentation has been updated (if applicable).
• There are no new warnings or errors from my changes.

Additional Context

#209