Review round two.
A restored timeline refuses a declared stream with no recorded sample
position instead of resuming it at zero, which would have restarted the
episode's audio clock silently.
A declared stream that produces no chunk for a transition now fails the
step. The contract does not say a chunk must exist; this slice requires
one, because a silently missing chunk cannot be told from a lost one.
Boundary 0 is exempt: no interval precedes it.
The fresh-epoch discontinuity refusal is dropped rather than written into
the amendment. Only the restore direction is stated, and sections 6 and 7
both have a fresh timeline publishing a discontinuity after a recovery or
a reset, so refusing the flag at an origin contradicted them. The dated
amendment now says the requirement is one-directional.
A snapshot with an unreadable chunk, or one whose handle is not attached,
is now unreadable as a whole rather than quietly carrying less audio than
was published. ViewPipeline::is_bootstrap_repeat is removed.
New tests: a missing chunk fails the step, restored timelines need every
declared stream's position, and a 7 Hz world's seven chunks sum to exactly
one second of 48 kHz samples. The bus-conformance reconnect row also cites
the test that actually replaces an incarnation.
Two readings of the section that are now checked rather than assumed: the
bootstrap window is exactly the boundaries where max(0, boundary - delay)
is zero and its repeated O[0] is the same artifact, and a chunk that
continues the previous one exactly cannot claim a discontinuity, which is
what keeps the restore rule checkable instead of advisory.