feat(data): wire sample report to real 87-DTC reference database

Created web/src/lib/dtc-fixtures.ts — the 5 DTC records displayed on
landing (P0420, P0301, P0171, P0442, P0700) now pull their factual fields
verbatim from backend/src/dtc_data.py:

  • description_en  (code title)
  • category         (pill)
  • common_causes[]  (probability bars)
  • diagnostic_steps[] (numbered procedure)
  • estimated_cost_min/max  (real DB ranges, e.g. P0420 = $200–$1,500)
  • labor_hours      (real DB hours)

Narrative fields (simple_explanation, technical_explanation, urgency
label, when_monitored, set_condition, multi-code correlation, freeze-
frame data, readiness monitors) remain hardcoded as Tier 2/3 "AI would
generate this at runtime" demo content until AI Key is wired.

Visibility:
  • SampleReport adds a "87-record OBD-II database" provenance line under
    the section header
  • Each Pro-view fault card now shows a green "DB REF ✓" badge next to
    the existing CHARM ✓ badge
  • Pro view has a small "DB" tag on the Probable Causes and Diagnostic
    Steps column headers to distinguish DB-sourced fields
  • DTCCarousel header gets the same "real DB" byline
  • Total repair cost strip now reflects real summed DB ranges

Total cost was $490–$990 (hand-tuned). Now $240–$1,885 (P0420 200-1500 +
P0171 30-300 + P0442 10-85 = real database math).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tsconfig.tsbuildinfo

@@ -1 +1 @@
-{"root":["./src/app.tsx","./src/main.tsx","./src/components/comparison.tsx","./src/components/dtccarousel.tsx","./src/components/faq.tsx","./src/components/footer.tsx","./src/components/hero.tsx","./src/components/pricing.tsx","./src/components/samplereport.tsx","./src/components/showcase.tsx","./src/components/testimonials.tsx","./src/lib/constants.ts"],"version":"5.9.3"}
+{"root":["./src/app.tsx","./src/main.tsx","./src/components/comparison.tsx","./src/components/dtccarousel.tsx","./src/components/faq.tsx","./src/components/footer.tsx","./src/components/hero.tsx","./src/components/pricing.tsx","./src/components/samplereport.tsx","./src/components/showcase.tsx","./src/components/testimonials.tsx","./src/lib/constants.ts","./src/lib/dtc-fixtures.ts"],"version":"5.9.3"}