Fix merge conflicts in PR #26 (probe re-exclusion fix) and merge

[mingles-agent]

Context

Issue #25 was closed as "Done" after agent review, but the implementing PR #26 has merge conflicts and was never actually merged. The fix is not in the codebase.

PR with conflicts: #26
Closed issue: #25
mergeable: CONFLICTING

What was fixed in this PR

When a node in PROBE state successfully completes an inference (RecordCBResult(success=true)), the old code deleted the CB entry entirely. When UpdateCBStateForBlock ran in EndBlock of the same block, Pass 2 found this node as HEALTHY with stale high miss-rate stats and immediately re-excluded it — undoing the probe recovery.

Fix: Added LastRestoredBlock int64 field to CircuitBreakerEntry. On probe success, instead of deleting the entry, set State=CBStateHealthy + LastRestoredBlock=blockHeight. In Pass 2, skip nodes where LastRestoredBlock == blockHeight (one-block grace period).

This was one of two reasons x0152 closed upstream PR gonka-ai#974:

"even a successful probe can get immediately undone in the same block"

Acceptance criteria

• Resolve merge conflicts in PR fix: prevent same-block re-exclusion after probe success #26 on branch feature/25-fix-probe-re-exclusion
• All tests pass (TestProbeSuccessNotReExcludedSameBlock, TestProbeSuccessCanBeExcludedNextBlock, TestProbeFailureReExcludesImmediately)
• PR merged to development branch
• Issue Fix: successful probe can be immediately re-excluded in the same block by EndBlock pass 2 #25 re-evaluated (was closed prematurely — verify the fix is sound)