feat: cache usdc balance

[justinenerio]

Changes

adds cache to usdc balance in shared preferences

Related issues

Fixes #1330

Checklist

• PR is ready for review (if not, it should be a draft).
• PR title follows Conventional Commits guidelines.
• Screenshots/video added.
• Tests added.
• Self-review done.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.50%. Comparing base (7c90034) to head (cf09662).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1348   +/-   ##
=======================================
  Coverage   79.50%   79.50%           
=======================================
  Files         187      187           
  Lines        4148     4148           
=======================================
  Hits         3298     3298           
  Misses        850      850           

Flag	Coverage Δ
solana-beta	79.50% <ø> (?)
solana-stable	79.50% <ø> (ø)

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