[FIX]: Model uses `std::string` for all types

[NikSimDev]

Version

v0.1.5

Severity

Minor (annoyanse)

Problem Description

// ID, JSON, numbers — all strings
std::map<std::string, std::string> attributes;

Problem:

• Loss of type information
• Slow conversions
• Possible errors (ID "123abc")

Solution: Use nlohmann::json:

template <typename Derived>
class Model {
    nlohmann::json attributes;  // Typed data
    
    template<typename T>
    T getAttribute(const std::string& key) {
        return attributes[key].get<T>();
    }
};

Verification

• I have searched for existing issues
• I am using the latest version
• I have provided a minimal reproduction