Fix infinite loop / OOM in proto reserved range parser

[dataCenter430]

Fixes: #8949

Summary

Fixes infinite loop and OOM when parsing proto reserved ranges that include the maximum field ID (65535). Addresses issue #8949.

Root cause

The loop in idl_parser.cpp (parsing e.g. reserved 0 to 65535) used voffset_t (uint16_t) as the loop counter. When id reached 65535, id++ wrapped to 0, so the condition id <= attribute remained true and the loop never exited, causing unbounded memory growth (CWE-835, CWE-400).

Fix

Use uint32_t for the loop counter so that after the last valid value (65535), id becomes 65536 and the loop terminates. Values are cast to voffset_t only when appending to reserved_ids.

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[dataCenter430]

Hi, I'm a big fan of google and I'm going to contribute here actively, as a contributor.
This is my first PR, so I really hope this will be merged. Since each PR is so important for me. 🙏
Best regards