fix readme and example

[xxibcill]

Description

remove example on README that doesn't work on BandChain, and edit example project to work properly.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code refactor
• Performance improvement
• Dependencies update
• Other (please describe):

Changes Made

• remove unusable code example on README
• update code on example project

Testing

• Added new unit tests
• Updated existing tests
• Manually tested with example projects
• No tests required (documentation only)

Test Configuration

• Node.js version:
• TypeScript version:
• Operating System:

Breaking Changes

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published

Additional Notes