Start at the factory, add PWA install and GPS real-world mode

The game now begins inside the Negin Sazan Pishgam Radmehr Atousa
vending-machine factory on the Mashhad–Chenaran road, and the world
extends ~20 km along the real driving route to Park Mellat and
Ferdowsi University.

- Factory compound: production hall with assembly line, office, yard,
  gate and company signs; first mission at its half-price demo machine
- Map data merged from four OSM extracts (factory zone, route corridor,
  region main roads, city zone), clipped to a 15 x 18 km region
- City meshes chunked and culled by distance; traffic recycled around
  the player; minimap and city map drawn from cached tiles + overview
- The Robot Market robot no longer walks with the family: it comes out
  of a machine when they arrive, greets them with expression portraits
  and goes back inside when they leave
- PWA: manifest, icons from the robot avatar, offline service worker
  generated at build time, install button / iOS steps, update prompt;
  Vazirmatn font bundled instead of Google Fonts
- Real-world mode: safety notice, GPS + compass tracking with accuracy
  smoothing, 20-40 m arrival radius, speed lock and in-person bonus

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

public/manifest.webmanifest

@@ -0,0 +1,20 @@
+{
+  "name": "عملیات مشهد · روبات مارکت",
+  "short_name": "روبات مارکت",
+  "description": "از کارخانهٔ نگین سازان پیشگام رادمهر آتوسا تا بوستان ملت: دستگاه‌های وندینگ روبات مارکت را در مشهد پیدا کن و امتیاز بگیر.",
+  "lang": "fa",
+  "dir": "rtl",
+  "start_url": "./",
+  "scope": "./",
+  "display": "fullscreen",
+  "display_override": ["fullscreen", "standalone"],
+  "orientation": "any",
+  "background_color": "#0d1412",
+  "theme_color": "#0d1412",
+  "categories": ["games", "education"],
+  "icons": [
+    {"src": "icons/icon-192.png", "sizes": "192x192", "type": "image/png", "purpose": "any"},
+    {"src": "icons/icon-512.png", "sizes": "512x512", "type": "image/png", "purpose": "any"},
+    {"src": "icons/maskable-512.png", "sizes": "512x512", "type": "image/png", "purpose": "maskable"}
+  ]
+}