Bounty marketplace UI (/, /bounties, /bounties/[id], /create)

[rylsherdamz-rgb]

Per SPEC.md §27. Landing, marketplace with filters, detail page with escrow status + claim, and create/fund form.

Acceptance:

• Browse + filter (tech, reward, asset, deadline, status)
• Create+fund calls create_bounty (escrow on creation)
• Detail shows on-chain status and claim button

[amine-bradji]

the bounty still stand ?