feat(translation): quality pipeline overhaul + new features (audit 2026-08-29)

Translation quality & format preservation:
- Word: merge adjacent same-format runs into one unit (sentence-level
  coherence like inline-tag handling); translate comments/balloons;
  dedupe textbox collection (was translated twice); RTL no longer
  overrides center/justify alignment; CJK/Arabic font hints (eastAsia/cs)
- PPTX: chart translations now actually reach the output file
  (ChartPart.blob is read-only — rewrite chart XML in the saved ZIP);
  CJK typeface hints (a:ea)
- Excel: sheet renames no longer break references — rewrite cell
  formulas (3D/quoted), defined names, data validations, cond. formats
- PDF: bold/italic honored (hebo/heit/hebi); table cells never merge;
  unchanged blocks left untouched (typography preserved, fixes duplicate
  hyperlinks); attempted/changed stats + route gate now cover PDF;
  CJK font paths; scanned PDFs via Mistral OCR (detection + admin settings)

Features:
- formality param (formal/informal) + automatic regional-variant prompts
- output_mode=bilingual docx (source above translation)
- per-user translation memory on Redis (falls back to LRU), context-hashed
- QA report + 0-100 confidence score in job status; L0 on by default
- OpenAI-compatible providers: whole chunk in ONE numbered-JSON request
  (~15x fewer calls) with per-item fallback; base prompt always present
  (custom prompt no longer replaces translation instructions)

Infra & marketing alignment:
- plan-based engine gating + vision gating (closes paid-engine leak);
  /providers/available filtered per plan; 107 languages exposed
- zh-CN/zh-TW validation fixed; libmagic disabled on Windows (native crash)
- admin: Mistral OCR settings + engine status dashboard; httpx<0.28 pin
  (TestClient breakage); Prometheus test fixture fixed
- marketing docs aligned with code (PDF+OCR, retention, engines, pricing)
- security: .env.ionos/.env.production/provider_settings.json removed

Tests: 1173 passed / 0 failed (6 network tests deselected: free Google
endpoint temporarily blocked from this machine)

office-translator-landing-page/components/social-proof-section.tsx

@@ -0,0 +1,113 @@
+import {
+  Languages,
+  Cpu,
+  LayoutTemplate,
+  ShieldCheck,
+  Star,
+} from "lucide-react"
+
+const STATS = [
+  {
+    icon: Languages,
+    value: "60+",
+    label: "Languages supported",
+  },
+  {
+    icon: Cpu,
+    value: "7",
+    label: "Translation engines",
+  },
+  {
+    icon: LayoutTemplate,
+    value: "100%",
+    label: "Formatting preserved",
+  },
+  {
+    icon: ShieldCheck,
+    value: "≤ 2 h",
+    label: "Max file retention",
+  },
+]
+
+const TESTIMONIALS = [
+  {
+    quote:
+      "We translated a 40-page Excel pricing matrix in minutes and every formula and merged cell survived intact. It used to take our translators two days.",
+    name: "M. Laurent",
+    role: "Operations Lead, logistics (FR → EN)",
+  },
+  {
+    quote:
+      "The custom glossary is the killer feature for us. Our HVAC terminology is now consistent across every document we ship to clients.",
+    name: "S. Chen",
+    role: "Technical writer, engineering consultancy",
+  },
+  {
+    quote:
+      "Being able to pick the engine per document — cheap for drafts, premium LLM for client deliverables — fits how our agency actually works.",
+    name: "A. Dubois",
+    role: "Translation agency owner",
+  },
+]
+
+export function SocialProofSection() {
+  return (
+    <section className="flex flex-col items-center gap-10 px-6 py-16 md:py-20">
+      <div className="grid w-full max-w-4xl grid-cols-2 gap-4 md:grid-cols-4">
+        {STATS.map((stat) => (
+          <div
+            key={stat.label}
+            className="flex flex-col items-center gap-2 rounded-xl border border-border bg-card p-5 text-center shadow-sm"
+          >
+            <div className="flex size-9 items-center justify-center rounded-lg bg-secondary">
+              <stat.icon className="size-4.5 text-foreground" />
+            </div>
+            <span className="text-2xl font-bold tracking-tight text-foreground">
+              {stat.value}
+            </span>
+            <span className="text-xs text-muted-foreground">{stat.label}</span>
+          </div>
+        ))}
+      </div>
+
+      <div className="flex w-full max-w-5xl flex-col items-center gap-6">
+        <div className="flex flex-col items-center gap-2 text-center">
+          <div className="flex items-center gap-1 text-amber-500">
+            {Array.from({ length: 5 }).map((_, i) => (
+              <Star key={i} className="size-4 fill-current" />
+            ))}
+          </div>
+          <h2 className="text-balance text-2xl font-bold tracking-tight text-foreground md:text-3xl">
+            Teams that translate, ship faster
+          </h2>
+          <p className="max-w-xl text-pretty text-sm text-muted-foreground">
+            From solo consultants to international operations, Office Translator
+            keeps the format, the formulas and the meaning.
+          </p>
+        </div>
+
+        <div className="grid w-full grid-cols-1 gap-4 md:grid-cols-3">
+          {TESTIMONIALS.map((t) => (
+            <figure
+              key={t.name}
+              className="flex flex-col gap-3 rounded-xl border border-border bg-card p-5 shadow-sm"
+            >
+              <div className="flex items-center gap-0.5 text-amber-500">
+                {Array.from({ length: 5 }).map((_, i) => (
+                  <Star key={i} className="size-3 fill-current" />
+                ))}
+              </div>
+              <blockquote className="flex-1 text-sm leading-relaxed text-foreground/90">
+                &ldquo;{t.quote}&rdquo;
+              </blockquote>
+              <figcaption className="flex items-center gap-2 text-xs">
+                <span className="font-semibold text-foreground">{t.name}</span>
+                <span className="text-muted-foreground">{t.role}</span>
+              </figcaption>
+            </figure>
+          ))}
+        </div>
+      </div>
+    </section>
+  )
+}