Implementation Plan for minimal_perfect_hash Policy

• Research and understand PtHash algorithm for minimal perfect hashing
• Implement proper PtHash algorithm based on the paper (https://dl.acm.org/doi/10.1145/3404835.3462849)
• Create minimal_perfect_hash.hpp policy file with all features
• Create comprehensive test file test_minimal_perfect_hash.cpp
• Allow up to 10% bucket waste per user request
  • Fixed table size calculation: (N * 11 + 9) / 10
  • Updated documentation: range is [0, 1.1*n-1]
  • Improved code readability with named constants
• Address all code review feedback
  • Removed trailing spaces from all files
  • Used anonymous namespace for uintptr definitions (file-local linkage)
  • Fixed potential overflow in group hash calculation
• Run security checks (no issues found)

Final Implementation:

✅ PtHash algorithm with two-level hashing
✅ 10% waste allowance for easier hash construction
✅ Named constants for all magic numbers (readability)
✅ Runtime checks support with control table
✅ Comprehensive tests for various scenarios
✅ Well-documented code with clear comments
✅ Clean formatting with no trailing spaces
✅ Proper encapsulation (anonymous namespace for internal types)
✅ Overflow-safe (uses uint32_t for group multiplier to prevent overflow)

The implementation is complete and production-ready!

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This section details on the original issue you should resolve

<issue_title>implement a minimal perfect hashing policy</issue_title>
<issue_description>Implement a new type_hash policy, minimal_perfect_hash, that is modeled after the existing fast_perfect_hash policy, except that it finds a perfect minimal hash function using the PtHash algorithm. The primary hash function is in the form H(x) = (M * x) >> N, where x is the value to hash (a type_id), and M and N are the integer parameters of the hash function. Like with fast_perfect_hash, if the runtime_checks policy is present in the registry, create a control table during initialization, and use it during hashing to check that the input value x is in the universe passed to initialize. Also create a test suite.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes implement a minimal perfect hashing policy #56

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