chore: initial commit for v0.0.1

DChain single-node blockchain + React Native messenger client.

Core:
- PBFT consensus with multi-sig validator admission + equivocation slashing
- BadgerDB + schema migration scaffold (CurrentSchemaVersion=0)
- libp2p gossipsub (tx/v1, blocks/v1, relay/v1, version/v1)
- Native Go contracts (username_registry) alongside WASM (wazero)
- WebSocket gateway with topic-based fanout + Ed25519-nonce auth
- Relay mailbox with NaCl envelope encryption (X25519 + Ed25519)
- Prometheus /metrics, per-IP rate limit, body-size cap

Deployment:
- Single-node compose (deploy/single/) with Caddy TLS + optional Prometheus
- 3-node dev compose (docker-compose.yml) with mocked internet topology
- 3-validator prod compose (deploy/prod/) for federation
- Auto-update from Gitea via /api/update-check + systemd timer
- Build-time version injection (ldflags → node --version)
- UI / Swagger toggle flags (DCHAIN_DISABLE_UI, DCHAIN_DISABLE_SWAGGER)

Client (client-app/):
- Expo / React Native / NativeWind
- E2E NaCl encryption, typing indicator, contact requests
- Auto-discovery of canonical contracts, chain_id aware, WS reconnect on node switch

Documentation:
- README.md, CHANGELOG.md, CONTEXT.md
- deploy/single/README.md with 6 operator scenarios
- deploy/UPDATE_STRATEGY.md with 4-layer forward-compat design
- docs/contracts/*.md per contract

client-app/package.json

@@ -0,0 +1,51 @@
+{
+  "name": "dchain-messenger",
+  "version": "1.0.0",
+  "main": "expo-router/entry",
+  "scripts": {
+    "start": "expo start",
+    "android": "expo start --android",
+    "ios": "expo start --ios",
+    "web": "expo start --web",
+    "lint": "eslint ."
+  },
+  "dependencies": {
+    "@react-native-async-storage/async-storage": "2.2.0",
+    "class-variance-authority": "^0.7.1",
+    "clsx": "^2.1.1",
+    "expo": "~54.0.0",
+    "expo-asset": "~12.0.12",
+    "expo-camera": "~16.1.6",
+    "expo-crypto": "~14.1.4",
+    "expo-clipboard": "~8.0.8",
+    "expo-constants": "~18.0.13",
+    "expo-document-picker": "~14.0.8",
+    "expo-file-system": "~19.0.21",
+    "expo-font": "~14.0.11",
+    "expo-linking": "~8.0.11",
+    "expo-router": "~6.0.23",
+    "expo-secure-store": "~15.0.8",
+    "expo-sharing": "~14.0.8",
+    "expo-splash-screen": "~31.0.13",
+    "expo-status-bar": "~3.0.9",
+    "expo-web-browser": "~15.0.10",
+    "nativewind": "^4.1.23",
+    "react": "19.1.0",
+    "react-native": "0.81.5",
+    "react-native-reanimated": "~3.17.0",
+    "react-native-safe-area-context": "~5.6.0",
+    "react-native-screens": "~4.16.0",
+    "react-native-worklets": "~0.8.1",
+    "tailwind-merge": "^2.6.0",
+    "tailwindcss": "^3.4.17",
+    "tweetnacl": "^1.0.3",
+    "tweetnacl-util": "^0.15.1",
+    "zustand": "^5.0.3"
+  },
+  "devDependencies": {
+    "@babel/core": "^7.25.2",
+    "@types/react": "~19.1.0",
+    "babel-preset-expo": "~13.0.0",
+    "typescript": "^5.3.3"
+  }
+}