Part of #4548 — second batch. This PR: docs/integrations/matrix.md
(18 hits), docs/agent-lifecycle/persistence.md (17 hits) = 35 more of
the 353 (99 total across the two PRs so far).
Same method as the first batch (#4551): minimal, meaning-preserving
active-voice rewrites only, no restructuring beyond what each flagged
sentence needed, no vale-off silencing.
Genuine false positives left in place, with per-file reasoning in the
PR body: predicate-adjective state descriptions ("is wedged", "is
stopped", "are unrelated", "is unaffected", "is needed"), one
design-intent idiom ("was meant to prevent" — same shape as earlier
docs-lint work), and one vale parsing artifact: "is read" flagged
inside the hyphenated compound adjective "read-only", not real passive
voice at all.