docs: add bounty rules for appeal fees and worker staking (#4)

docs/bounty-rules.md

@@ -0,0 +1,28 @@
+# Bounty Rules — Appeal Fees and Worker Staking
+
+This document describes the appeal and staking mechanics introduced in ProofWorks Phase 9.
+
+## Appeal Bond
+
+When a worker disputes a bounty verdict, an **appeal bond** is required.
+
+- The appeal bond is **20% of the task reward**.
+- The bond is locked at the time the appeal is filed.
+- If the appeal is **upheld** (the worker wins), the bond is returned in full.
+- If the appeal is **rejected** (the original verdict stands), the bond is forfeited and distributed to the original task creator.
+
+## Worker Staking
+
+Workers must stake GEN tokens when claiming a bounty task.
+
+- The worker stake is **forfeited if the claim expires without a proof submission**.
+- This ensures workers only claim tasks they intend to complete.
+- The stake is returned when the worker submits a valid proof or when the bounty is resolved.
+
+## Summary
+
+| Action | Amount | Outcome |
+|--------|--------|---------|
+| File appeal | 20% of reward | Bond locked; returned if upheld, forfeited if rejected |
+| Claim task | Worker stake | Locked until proof submission or resolution |
+| Expire without proof | Worker stake | Forfeited |