feat(pdf): brand kit foundation for @react-pdf/renderer

Phase 1 / commit 1 of 14 — installs deps and lays down the brand-kit
primitives used by every internal-only PDF. No callers wired yet.

Adds:
  @react-pdf/renderer 4.5.1   one engine for internal exports
  unpdf 1.6.2                 reserved for berth-PDF parser tier-2
  react-image-crop 11.0.10    admin logo crop UI (commit 2)
  svgo 4.0.1                  SVG sanitization on logo upload (commit 2)

brand-kit/
  tokens.ts          single source of truth for colors/fonts/spacing
  logo.ts            resolvePortLogo() — cached, soft-fallback
  DocumentShell      <Document><Page> + fixed Header + fixed Footer
  Header             dark band, logo slot (letterboxed) + text fallback
  Footer             page N of M + generated-at + confidential tag
  Section            heading + bottom border
  KeyValueGrid       2-col (default) or stacked label/value
  DataTable          zebra rows + sticky header + totals row + empty state
  Badge              5 tone pills
  charts/
    BarChart         pure SVG, 4-tick y-axis, optional value labels
    LineChart        pure SVG, line + markers + grid
    PieChart         pure SVG, donut-or-pie + side legend
    FunnelChart      pure SVG, slope-cut slices for pipeline stages

render.ts            renderToBuffer + renderToStream wrappers, typed

svg-primitives.tsx   <SvgLabel> wraps react-pdf SVG <Text> to bridge
                     missing TS declarations for fontSize/fontFamily

Smoke test renders a kitchen-sink Document including every primitive
and every chart, plus an empty-data path. 1293+4 vitest tests green.

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

package.json

@@ -57,6 +57,7 @@
     "@radix-ui/react-tabs": "^1.1.13",
     "@radix-ui/react-tooltip": "^1.2.8",
     "@react-email/components": "^1.0.12",
+    "@react-pdf/renderer": "^4.5.1",
     "@socket.io/redis-adapter": "^8.3.0",
     "@tanstack/query-broadcast-client-experimental": "^5.100.10",
     "@tanstack/react-query": "^5.100.10",
@@ -97,15 +98,18 @@
     "react-easy-crop": "^5.5.7",
     "react-email": "^6.1.3",
     "react-hook-form": "^7.75.0",
+    "react-image-crop": "^11.0.10",
     "recharts": "^3.8.1",
     "sharp": "^0.34.5",
     "socket.io": "^4.8.3",
     "socket.io-client": "^4.8.3",
     "sonner": "^2.0.7",
+    "svgo": "^4.0.1",
     "tailwind-merge": "^3.6.0",
     "tailwindcss-animate": "^1.0.7",
     "tesseract.js": "^7.0.0",
     "ts-pattern": "^5.9.0",
+    "unpdf": "^1.6.2",
     "vaul": "^1.1.2",
     "web-vitals": "^5.2.0",
     "zod": "^4.4.3",