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

docs/api.md

@@ -1,4 +1,4 @@
-# pysim-otaman-server — HTTP API reference
+# pysim-simple-server — HTTP API reference
 
 The server exposes a JSON HTTP API under `/api/*`. All responses carry
 `Access-Control-Allow-Origin: *` (plus `Access-Control-Allow-Private-Network: true`
@@ -6,7 +6,7 @@ on the preflight), so the API is reachable from a separately-hosted PWA.
 
 ## Version compatibility
 
-| Server | PWA (OTAMan) | Status |
+| Server | PWA (SIMple) | Status |
 |--------|-------------|--------|
 | 1.x.x | 1.x.x | ✅ Compatible |
 | 0.x.x | 1.x.x | ❌ Outdated — update server |