feat: Implemented Gas Compute Budget Guards for Long running Loops

[Oluwaseyi89]

Description

This PR implements gas/compute budget guards for long-running loops across the contract codebase. It introduces chunked operations, maximum iteration limits, and comprehensive testing to ensure all dynamic collections (investors, periods, etc.) stay within safe compute bounds.

Key Changes

• Loop Auditing: Identified and annotated all loops over dynamic collections with maximum size limits
• Chunked Operations: Implemented new entrypoints (distribute_chunk, etc.) that process bounded slices of data
• Gas Safety: Added explicit iteration limits and early termination checks in all loop structures
• Bug Fixes: Resolved existing syntax errors and logical bugs discovered during the audit process
• Testing: Added comprehensive chunking_tests.rs with high-load scenarios that verify resource usage boundaries
• Documentation: Updated README and code comments to describe chunking contracts and off-chain orchestration

Technical Details

• Created bounded iteration patterns with configurable chunk sizes
• Implemented cursor-based pagination for all list operations
• Added read-only methods for off-chain systems to plan execution
• Maintained 95%+ test coverage with worst-case scenario validation
• Fixed compilation warnings and improved error handling

Testing

• ✅ All tests pass (cargo test)
• ✅ New chunking tests simulate high-load scenarios
• ✅ Verified termination within expected resource bounds
• ✅ Maintained backward compatibility with existing interfaces

Closes #113

[Oluwaseyi89]

@thlpkee20-wq errors from the previously merged PRs are much. My original implementation are error free.