[Haoming9527]

Part of #872. Stacked on #923.

What was wrong

Session result-cache cleanup started additional one-shot host workers during teardown. Root disposal could also withdraw the current policy lookup before pending cleanup finished. Migrating concurrent expiry directly to the resident connection exposed its unchanged 32-request limit: forty simultaneous Session expiries completed only 32 purges.

The change

Send the existing typed result/purge envelope through the owning resident client. Retain public policy and sandbox dependencies through cleanup, resolve current authority before and after grant preparation, and preserve native storage/no-follow checks. Stop ordinary admission, join pending Session cleanup, then close the connection. Sequence only each owner's existing cache cleanup section; refusal releases the next Session. Missing authority, changed grants or incomplete cleanup remain explicitly deferred without a replacement worker.

Package-root and standalone integrations use the same lifecycle. Bilingual docs and changelog describe the boundary and remaining #872 requirements.

Validation

• Build/typecheck, diff check and file-size gate pass: 935 tracked code files, all at or below 1000 lines.
• After normal-merging the upstream composition-boundary fix 3fd7253d, build and size checks passed; 19 checks / 3 focused suites passed (publication boundary, moved session provider, real cleanup), followed by the updated cancellation fixture 1/1 on Windows. Its POSIX resident-purge assertion will run in the new cross-platform CI.
• Initial affected Windows run: 89 checks / 10 suites passed, 0 failed, 0 skipped.
• After stacking on the final feat(shell): expose gated persistent sessions through Native and PTC #923 base, the combined-worker run below passed 67 checks / 7 suites, 0 failed, 0 skipped. These overlap the initial run.
• Actual public Agent/Session, Policy, Sandbox and Subprocess checks keep one host kernel spawn through file calls and disposal, join held cleanup before exit, preserve a sibling consumer, and reject a replaced cache directory without touching its external target.
• Meaningful negatives retained: forty expiries produced 32/40 before cleanup sequencing; removing only the retained-authority hook from a separate compiled copy failed the root check with 0/2 caches purged. The standalone and no-follow checks still passed. Removing only the duplicate client drain did not fail because dependency disposers also join cleanup; this ineffective control and fixture setup failures are recorded separately.

npm run build
build: compiled src/ to lib/ and copied 60 assets

node scripts/check-file-size.mjs
check-file-size: 935 code file(s) checked, all at or under 1000 lines

node test/run.mjs resident-result-cleanup resident-kernel result-lifecycle result-cleanup-authority result-storage-host result-storage-cache-prep resident-shell-channel
dsh-ops test: 7 suite(s) passed in 40s

Combined worker SHA-256: 9b25fceacb73ab1abe53b64b291b89d8ee8896cb9d8df6cfa7a1983f993715c0.
Latest pull-request CI: Cross-platform validation / CI required — passed all 10 jobs for 943c5bc9. The earlier run reported the upstream publication-boundary violation and a stale POSIX cancellation fixture expecting a one-shot purge. The ordinary upstream merge and test-only followup address those separately; the failed evidence is retained. This is a draft slice, not full #872 acceptance.

Environment

Windows x64, Node v26.12.1, locked development dependencies. Stacked on #923; includes upstream composition fix 3fd7253d through ordinary merge 8a2cbeb9, followed by test-only commit 943c5bc9. No dependency, version, model-facing schema or prompt changes.