refactor(architecture): implement 2026-09-18 decisions

[DavidHLP]

Summary

Implements the adopted architecture decisions from the 2026-09-18 ResiCache reports:

• P0: make internal runtime bean assembly single-source; keep the chain factory as the only chain owner.
• P1: share the writer async submission lifecycle through one private helper while preserving common-pool execution, snapshot/MDC capture, resolver cleanup, and exceptional futures.
• P2: lock the writer/chain write-back failure telemetry count-once boundary with characterization and Redis-down tests.
• ADR-0001 §15 now explicitly limits read-through write-back telemetry to failures that go through the writer PUT chain; LoaderOrchestrator does not report a second time.

The report's A3 migration split and A4 annotation re-ownership remain deferred; A5 writer result/statistics module remains closed as YAGNI.

Tickets

Closes #19
Closes #20
Closes #21
Closes #22

Verification

• Focused P0/P1/P2 unit tests: 55 tests, 0 failures/errors.
• ./mvnw -Punit test -B: 718 tests, 0 failures/errors.
• ./mvnw clean verify -B: final remote run ended with BUILD SUCCESS, __MAVEN_RC__=0, 914 tests, 0 failures/errors, and all JaCoCo coverage checks met. An earlier non-clean report showed a class/execution-data mismatch and was not used as coverage evidence.
• ./mvnw checkstyle:check -B: 0 Checkstyle violations.
• bash scripts/ci/check-test-names.sh: passed.
• Redis integration tests use Testcontainers and passed with Docker available.
• Final read-only code review: PASS; no findings.
• GitHub CI for d989991: 10 checks passed, 0 failed.

Checklist

• New behavior has tests; bug fixes have a regression test.
• Integration tests touching Redis extend AbstractRedisIntegrationTest (Testcontainers — Docker must be running).
• bash scripts/ci/check-test-names.sh passes; integration classes do not use *IT.java.
• No over-engineering: features that belong in Resilience4j or Caffeine are out of scope.
• Javadoc on public API; Chinese rationale comments are welcome for design decisions.
• Commit messages follow Conventional Commits.

Backward compatibility

No public API, new dependency, public executor/event SPI, retry/backoff, metric tag, cache outcome, or serialization protocol change is intended. The A0 change removes redundant internal imports only; A1 is a private helper extraction; A2 documents and tests the existing writer/chain reporter ownership without adding a second reporter path.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-18T09:54:42.475010Z	d989991	New commits

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