add memo builder fun to tx builder

[Fraccaman]

Describe your changes

Checklist before merging

• If this PR has some consensus breaking changes, I added the corresponding breaking:: labels
  • This will require 2 reviewers to approve the changes

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 6 lines in your changes missing coverage. Please review.

Project coverage is 72.70%. Comparing base (b0b41dc) to head (605fa4c).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/sdk/src/args.rs	0.00%	6 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3809      +/-   ##
==========================================
- Coverage   72.71%   72.70%   -0.02%     
==========================================
  Files         338      338              
  Lines      104487   104493       +6     
==========================================
- Hits        75977    75967      -10     
- Misses      28510    28526      +16     

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