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/components/ui/Input.tsx

@@ -0,0 +1,34 @@
+import React, { forwardRef } from 'react';
+import { TextInput, View, Text, type TextInputProps } from 'react-native';
+import { cn } from '@/lib/utils';
+
+interface InputProps extends TextInputProps {
+  label?:     string;
+  error?:     string;
+  className?: string;
+}
+
+export const Input = forwardRef<TextInput, InputProps>(
+  ({ label, error, className, ...props }, ref) => (
+    <View className="w-full gap-1">
+      {label && (
+        <Text className="text-muted text-sm font-medium mb-1">{label}</Text>
+      )}
+      <TextInput
+        ref={ref}
+        placeholderTextColor="#8b949e"
+        className={cn(
+          'bg-surfaceHigh border border-border rounded-xl px-4 py-3 text-white text-base',
+          error && 'border-destructive',
+          className,
+        )}
+        {...props}
+      />
+      {error && (
+        <Text className="text-destructive text-xs mt-1">{error}</Text>
+      )}
+    </View>
+  ),
+);
+
+Input.displayName = 'Input';