[sagar-kap]

Completes Bulgarian Parts 1–4, extends Part 5 through chapter 15, and repairs structural, terminology, metadata, and citation defects found by adversarial review.

Also closes the small pre-Part-9 source gaps for German, Spanish, French, Portuguese, Turkish, and Ukrainian, plus the missing Portuguese/Turkish/Ukrainian Part 6 commentary chapters.

Tooling hardening:

• align repeated translation keys by occurrence
• require full item parity for AI-translated consolidated Q&A
• validate localized ToC title coverage
• use a stable client hydration marker in Playwright

Verification:

• multilingual polycheck and independent citation/gematria checks
• exact tag, link, and metadata parity audits
• task check (92 test files, 1,174 unit tests; 6,397 prerendered routes; 11 Playwright tests)