fix: close preview and idle hibernate gaps

[CMGS]

Summary

• route every preview request through live-claim authorization, activity stamping, wake serialization, and a fresh guest dial
• reject idle-hibernate settings on egress pools, which cannot resume safely
• align deploy docs and audit event naming with the implemented contract

Why

Guest connection pooling let a reused preview request skip PreviewDial. If idle hibernation had already entered its transition, that request could reach the stopped connection instead of waiting for wakeResolved; non-replayable requests could fail. The narrow fix removes guest-side keep-alive reuse instead of adding connection generations or more lifecycle state.

Egress pools accepted idle-hibernate configuration even though Hibernate intentionally rejects that lane, so the setting could never provide the documented behavior.

This PR is stacked on #81 and contains one commit.

Validation

• make go-test
• GOLANGCI_LINT_CACHE=/tmp/sandbox-pr81-golangci-cache make go-lint
• GOOS=linux|darwin GOWORK=off asl ./... across all Go modules
• macOS: make lint && make test
• Linux Rust container: rustfmt, clippy with -D warnings, and tests for boot/init and silkd

[CMGS]

Squash-merged into codex/close-repo-review as 4183bb3, together with the residual this PR's config gate could not reach: the node-wide idle sweep still selected unpooled egress claims (template/checkpoint claims on the egress lane), which hibernateLocked then refused every tick. idleOnce now skips the lane outright.

No test rides that last part: hibernateLocked returns ErrNoEgressHibernate before touching any state, so a mutation test confirmed no state-level assertion can tell the two behaviours apart — the only symptom was a logged error per sweep. The invariant itself stays covered by TestEgressLaneDoesNotHibernate.

Reviewed and agreed on the preview reasoning: the pooled path bypassed Transition, which is the only serialization point between a claim and its own hibernation. Closing in favour of the squashed commit.