feat: add units to balances

[LesnyRumcajs]

Summary of changes

Changes introduced in this pull request:

• added units to balances,
• limit balances to two decimal digits (we don't care about smaller units and copying humantoken from Forest would be an overkill)

Reference issue to close (if applicable)

Closes #70

Other information and links

Change checklist

• I have performed a self-review of my own code,
• I have made corresponding changes to the documentation. All new code
  adheres to the team's
  documentation standards,
• I have added tests that prove my fix is effective or that my feature works
  (if possible),

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 59.25926% with 11 lines in your changes missing coverage. Please review.

Project coverage is 11.04%. Comparing base (5975f2b) to head (fc4b8f7).

Files with missing lines	Patch %	Lines
src/faucet/controller.rs	0.00%	7 Missing ⚠️
src/faucet/views.rs	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##            main     #109      +/-   ##
=========================================
+ Coverage   9.88%   11.04%   +1.15%     
=========================================
  Files         25       25              
  Lines       1163     1186      +23     
=========================================
+ Hits         115      131      +16     
- Misses      1048     1055       +7     

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