v1.0.32 — Amber login via native Capacitor plugin

- Replaced all URL-scheme hacks with nostr-signer-capacitor-plugin
- Plugin uses native Android intents directly — no nostrsigner: URL, no intent: URL, no encoding issues
- This is how Coracle and other proper Capacitor apps do it
- Requires: npm run android:build && cap sync android (plugin needs native sync)
