refactor: update EOF validation logic and improve error handling

[jackwener]

• line 54 don't check MAX_INITCODE_SIZE
• use validate_raw_eof_inner to simplify Eof::decode+validate_eof_inner

[codspeed-hq]

CodSpeed Performance Report

Merging #2304 will not alter performance

_{Comparing jackwener:check_len (4893346) with main (3811df6)}

Summary

✅ 8 untouched benchmarks

[rakita]

nice change!