refactor: optimize Vec push avoid realloc mem

[nkysg]

Description

optimize Vec push avoid realloc mem

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PR author checklist:

• Added changelog entry, using unclog.
• Added tests.
• Linked to GitHub issue.
• Updated code comments and documentation (e.g., docs/).
• Tagged one reviewer who will be the one responsible for shepherding this PR.

Reviewer checklist:

• Reviewed Files changed in the GitHub PR explorer.
• Manually tested (in case integration/unit/mock tests are absent).

[codecov]

Codecov Report

Attention: Patch coverage is 8.33333% with 11 lines in your changes missing coverage. Please review.

Project coverage is 66.87%. Comparing base (5bba36e) to head (8041036).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
...s/ics721-nft-transfer/src/handler/send_transfer.rs	0.00%	10 Missing ⚠️
.../ics721-nft-transfer/src/handler/on_recv_packet.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1374      +/-   ##
==========================================
- Coverage   66.88%   66.87%   -0.02%     
==========================================
  Files         225      225              
  Lines       22617    22622       +5     
==========================================
+ Hits        15127    15128       +1     
- Misses       7490     7494       +4     

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[Farhad-Shabani]

Thank you @nkysg for the improvement, and your first contribution!

[nkysg]

Thanks for help @rnbguy @Farhad-Shabani