fix(sessions): prevent excess cleanup after disk pressure clears (#143285)

Historical planning and reclamation no-ops, and declined cap-archived entry
removal, kept the previous physical-byte total. Another operation could free
enough space while an attempt was skipped, yet cleanup still deleted the next
eligible history or archived session.

Remeasure after the lifecycle and writer holds release, share one historical
no-op outcome, and preserve measurement errors, protection checks, archive
ordering and configured targets. Document the stopping behavior.

Eight controlled-interleaving regressions cover planning, materialization,
real reclamation Workers and archived entries, including measurement errors.
Focused eviction and ownership suites pass 56 tests; changed checks and an
independent P0-P2 review pass.