rename OTAMan → SIMple (v2.3.0)

- package pysim_otaman_server → pysim_simple_server; distribution and
  console script pysim-otaman-server → pysim-simple-server
- PWA branding SIMple: title, header, manifest, help EN/RU, GitHub links
- localStorage keys otaman_* → simple_* (clean break, no migration)
- export filenames simple-cards.json / simple-custom-files.json
- service worker cache simple-v189
- README/docs/setup/start scripts updated; no 'otaman' left in the tree

frontend/manifest.json

@@ -1,6 +1,6 @@
 {
-  "name": "OTAMan",
-  "short_name": "OTAMan",
+  "name": "SIMple",
+  "short_name": "SIMple",
   "description": "Offline APDU helper for SIM/USIM/RAM commands",
   "start_url": "index.html",
   "display": "standalone",