fix(playbook): preserve managed shimmer until lifecycle settles

[edwin-zvs]

Summary

• remove the 10-minute expiry from agent-managed Playbook runs across daemon, TUI, and web clients while retaining it for untouched optimistic runs
• settle delegated pending blocks when their referenced session terminates, including eager archive and delete cleanup; remove the run when the last delegated block settles
• document the lifecycle contract and retain the numeric expiry field for wire compatibility

Verification

• cargo test -p construct-daemon playbook -- --nocapture (117 passed)
• cargo test -p construct-cli playbook -- --nocapture (340 passed)
• cargo test -p construct-protocol (105 passed, 1 sandbox-dependent test ignored; doc test passed)
• focused managed-expiry and archive/delete lifecycle tests after rebasing onto current main
• embedded web JavaScript parsed with node --check
• cargo build
• git diff main...HEAD --check

No recording: this changes lifecycle behavior without introducing a visually distinct UI state.