Add original bounty workflow poem

[TodouWisiper]

/claim #76

Summary

• Add an original poem as POEM.md in the repository root.
• Keep the change scoped to the single requested Markdown file.

Creative Decision

I used a warranty-ledger theme because this project centers on trusted freelance/bounty workflows: scope, proof, review, and payout. The poem uses four concise quatrains so each stanza maps to one checkpoint in that workflow.

Validation

• git diff --check HEAD~1 HEAD passed.
• POEM.md has 4 stanzas, exceeding the 3-stanza minimum.
• I attempted npm test, but the root test script recursively re-invoked npm run test -w apps/api with accumulating workspace arguments and failed before running useful tests; this PR only adds Markdown content.

Closes #76

[Adamchaua]

Monitoring this PR. For payout: EVM 0x1ecab01075f3bdf1b56b7d849c8e28ef88943624; PayPal ckelvinkhanh32@gmail.com.