feat: ship Concierge V2 and editorial perfume hero - #5

Summary

• Replace the fixed Concierge V1 fallback with a typed multi-turn perfume intelligence pipeline that separates general knowledge, live Fádé catalogue evidence, approved knowledge, reviews, and current web research.
• Add real streaming adapters and bounded fallback for OpenAI, Anthropic, Gemini, and xAI, with safe citations, URL validation, model cost accounting, spend gates, durable production limits, and provider health telemetry.
• Add owned conversation history, feedback, guest entitlement, catalogue revalidation, admin observability, and a responsive desktop/tablet/mobile concierge workspace.
• Add an editorial homepage perfume slideshow with accessible controls, reduced-motion handling, swipe support, and curated imagery.
• Deploy the additive Concierge V2 Prisma migration to the configured database.

Test Coverage

• AI-assessed branch coverage: 60% (18/30 traced code paths), meeting the 60% minimum; 12 lower-priority integration/eval paths remain documented.
• Tests: 46 to 47 test files (+1 provider coverage file during the ship gate).
• Final Vitest result: 39 files, 305 tests passed.

Pre-Landing Review

• Fixed a critical guest-ownership bug: the conversation creation API now returns the new HTTP-only identity cookie, so a guest can reopen and archive the conversation it just created.
• No remaining SQL/data-safety, LLM trust-boundary, ownership, or frontend checklist blockers found.

Design Review

• Lite source review found no blocking design issues.
• Browser verification passed across desktop Chromium, tablet Chromium, mobile Chromium, and mobile WebKit, including 320px overflow, dark/light themes, and a desktop axe pass.

Plan Completion

• 32 of 50 audited implementation items are complete.
• 14 items are partial or intentionally deferred, including research caching/deduplication, guest-to-account transfer, expanded history controls, merchant knowledge management, richer response blocks/actions, and remaining admin runtime controls.
• 4 items require follow-up preview/manual verification, including all-provider citation behavior, authenticated multi-session ownership, concurrent guest behavior, and deeper screen-reader/deployed-theme testing.
• The migration and live configured-database smoke tests are complete. Two genuinely different educational questions streamed distinct answers, and a guest conversation was created, reopened, and archived successfully.

Verification Results

• npm run typecheck
• npm run lint
• npm test (305 passed)
• npm run build (64 generated routes)
• npx prisma validate
• npx prisma migrate deploy
• npx prisma migrate status (schema up to date)
• Concierge Playwright suite (13 passed, 3 intentional duplicate axe skips)
• Live allowance/history endpoints, streaming answers, cookie ownership, reopen, and archive checks

Documentation

• README.md: added Concierge V2 capabilities, provider and environment configuration, API routes, validation commands, and links to the dedicated documentation set.
• docs/CONCIERGE_V2_AUDIT.md: corrected the audit date, branch/commit state, tracked test status, and pull-request status.

Documentation Debt

• The editorial homepage slideshow has no dedicated reference or explanation document; existing hero handoffs describe the earlier Stage 1/orbit implementations. Track this as follow-up documentation debt.

Test plan

• Unit and database integration tests pass.
• Production build passes.
• Responsive, theme, and accessibility browser checks pass.
• Configured database migration and live Concierge V2 smoke checks pass.