_ebpf_pe_get_map_definitions is fragile

The function _ebpf_pe_get_map_definitions is fragile in how it parses map data from PE images and handles long map names. It should use the offset of the first long string to determine the end of the maps section instead of relying on an unreliable heuristic.

For now, it appears to work, but if map_entry_t format changes it may break again.

Locate _ebpf_pe_get_map_definitions and inspect how it parses map data from PE images, including map_entry_t and long map names. Compare the current heuristic with the offset of the first long string, then validate the revised boundary handling against the PE image cases available in the repository; done means the parser no longer relies on that heuristic.

Written by the indexing model from the issue text.