feat: stream/bet stability integration

[rndrntwrk]

Summary

This is the Hyperbet consumer-side half of the stream-to-bet sync upgrade.

It hardens the betting consumer around authoritative source truth from Hyperscapes, preserves settlement truth across rollover, and upgrades the soak/capture lane so the source arena, embedded stream, and market state can be audited together.

Associated Hyperscapes source PR: HyperscapeAI/hyperscape#1065

What This Adds

• keeper-side source-truth surfaces for the betting consumer: /api/arena/prediction-markets/overview and /api/sync/status
• consumer handling for live plus recentSettlement, so the finished duel remains visible through proposal, dispute-window, finalization, and claim flow while the next duel becomes live
• renderer-health and degraded-state handling in the consumer so Hyperbet does not present a healthy stream when the source renderer is still stuck on initialization/finalizing
• local soak upgrades that capture three synchronized views per cycle: standalone source arena, embedded Hyperbet stream, and Hyperbet market truth
• duel-key normalization, drift detection, and runtime hardening around the live betting surface
• evidence-driven UI cleanup to keep the stream/bet additions aligned with the existing page pattern rather than introducing a second visual system

Why This PR Exists

The old consumer lane was too projection-centric. It could prove keeper consistency with itself, but not always that the effective source stream, embedded stream, and active market were all telling the same truth through a duel handoff.

This PR keeps Hyperbet on the consumer side of that contract: consume the authoritative source feed, expose explicit sync health, and preserve the prior duel’s settlement truth instead of dropping it during rollover.

Validation

• Hyperbet CI / PM gate coverage on the branch
• local soak artifacts for source arena, embedded stream, and market overview
• rollout hardening for the local lane while staged tri-chain signoff remains authoritative

Draft / Merge Notes

This PR should remain draft until the paired Hyperscapes source PR and the end-to-end soak both pass together.

Do not merge this PR independently of HyperscapeAI/hyperscape#1065.