feat(example): add quick-test-swap (tBNB → CAKE) with docs and scripts

[kuwiez]

Description

This PR adds a new example Quick Test Swap that demonstrates a minimal end-to-end token swap on BNB Smart Chain Testnet.
It includes both:

• A local AMM (constant product x * y = k) simulation.
• A real on-chain swap using the PancakeSwap V2 Router (tBNB → CAKE).

The example also includes slippage checks, clean formatting via Prettier, and documentation in README.md.

Type of change

• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

• Ran local simulation with:

  npx ts-node index.ts --chain local --amount 1 --slippage 0.5

✅ Produced expected swap output with correct math.
Ran live testnet swap with:
npm run swap:testnet -- --execute true
✅ Transaction successfully mined on BSC Testnet:
Txn submitted: 0xee5cac4db4f6a2c9c61a2effc51acbab9ef79bcd8553402a278fb98af2889ddf
Mined in block 65714391

• 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

[futures996]

OK

[futures996]

E AÍ COMUNIDADE BNB SMART CHAIN!!