🧹 [Refactor excessively long function register_collections]

[Tcode-Motion]

🎯 What: The register_collections method in stdlib/src/collections.rs was a single massive function that initialized and registered all the standard library collection functions. This refactoring breaks it down into register_list_functions, register_common_functions, and register_map_functions.
💡 Why: By extracting the logic into logically grouped helper functions, we improve readability, and maintainability.
✅ Verification: Verified by compiling via cargo check and cargo clippy, and passing the full test suite with cargo test --workspace.
✨ Result: The register_collections method is now short and clearly conveys its intent.

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PR created automatically by Jules for task 12164195751029798500 started by @Tcode-Motion

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