Fix memory leak from repeated ProjDataInfo::clone() calls

[NikEfth]

This PR fixes a memory leak detected by AddressSanitizer in ScatterSimulation::set_template_proj_data_info. The issue was caused by calling arg.clone() multiple times inside dynamic_cast expressions, leading to leaked heap allocations when the cast failed.

The fix: • Calls clone() exactly once • Transfers ownership safely using a smart pointer • Preserves the existing runtime type checks for supported ProjDataInfo types

This change is purely a memory-safety fix and does not alter behaviour or interfaces.

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Testing performed

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• [X] I have performed a self-review of my code
• [] I have added docstrings/doxygen in line with the guidance in the developer guide
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[NikEfth]

Based on CODACY suggestion I simplified a bit the set_template_proj_data_info() to use the shared_ptr