docs: define D1.4 two-book product architecture

[sunpole]

Цель

Завершить architecture-only этап D1.4: определить безопасную работу uDream с двумя исходными книгами до extraction второй базы и до любой реализации selector, combined search или side-by-side comparison.

Что добавлено

• docs/TWO_BOOK_ARCHITECTURE.md;
• machine-readable docs/two-book-architecture.json;
• permanent scripts/validate-two-book-architecture.mjs;
• CI-проверка архитектурного контракта;
• factual patchnote 23.8.11;
• новый real PNG, относящийся именно к D1.4.

Главные решения

• default остаётся ru-current-v1;
• второй сохранённый PDF пока не является registered dataset;
• global identity: (dataset_id, record_id);
• первый будущий режим — separate dataset switching;
• combined search — federated по отдельным indexes без destructive JSON merge;
• comparison — только через explicit reviewed relation map;
• URLs, history и sharing сохраняют dataset identity;
• activation атомарная, с автоматическим fallback к ru-current-v1;
• unrelated origin caches не затрагиваются.

Границы

Не изменяются:

• существующие файлы data/;
• runtime и PWA;
• Service Worker и package metadata;
• versions/;
• _archive/;
• текущие 4 086 записей.

Проверки

• regression tests;
• project/provenance/registry/audit validators;
• new two-book architecture validator;
• patchnote/new-image validation;
• JavaScript syntax checks;
• полный review changed files и protected paths перед merge.

Issue

Closes #30 после успешного merge и финального READY-handoff.

[chatgpt-codex-connector]

💡 Codex Review

https://github.com/sunpole/udream/blob/24bf2f828368ecd7a07a67e94699d7bd879c6c37/docs/two-book-architecture.json#L346-L350
Include activation failure in automatic fallback

The human-readable contract requires automatic fallback for an activation failure, but the machine-readable automatic_on list omits that condition. A failure after validation while atomically activating a new dataset would therefore have no mandated recovery path for future consumers of this JSON (and the new validator does not detect the mismatch), despite the architecture's required stable-fallback behavior; add and validate an activation-failure trigger.

AGENTS.md reference: AGENTS.md:L219-L225

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[chatgpt-codex-connector]

Synchronize all project status documents

Marking D1.4 complete here leaves the repository's other current-state sources contradictory: README.md still reports the 23.8.10 baseline and says D1.4 is next, docs/PRODUCT_VISION.md, docs/PROJECT_STATE.md, and docs/TRANSLATION_WORKFLOW.md likewise still present D1.4 as pending, and CHANGELOG.md has no 23.8.11 entry. This can send the next handoff or planning task down an already-completed phase; update those maintained documents together with this milestone.

AGENTS.md reference: AGENTS.md:L199-L203

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