release: v4.8.10 user-configurable STUN/TURN servers

- add header gear + connection-screen entry points to Advanced network settings
- render the ICE settings modal at the app root (reachable from any screen via event)
- remove the standalone relay-only toggle/description from the start screen
  (relay-only now lives in the advanced settings panel)
- fix crash from referencing main-component state inside EnhancedConnectionSetup
- bump version to 4.8.10 across header, manifest, README, init message, disclaimer
- document the feature in CHANGELOG and README

manifest.json

@@ -1,5 +1,5 @@
 {
-  "name": "SecureBit.chat v4.8.9 - ECDH + DTLS + SAS",
+  "name": "SecureBit.chat v4.8.10 - ECDH + DTLS + SAS",
   "short_name": "SecureBit",
   "description": "P2P messenger with ECDH + DTLS + SAS security, military-grade cryptography and Lightning Network payments",
   "start_url": "./",