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

node/explorer/validators.js

@@ -0,0 +1,58 @@
+(function() {
+  var C = window.ExplorerCommon;
+
+  async function loadValidators() {
+    C.setStatus('Loading…', 'warn');
+    try {
+      var data = await C.fetchJSON('/api/validators');
+      var validators = (data && Array.isArray(data.validators)) ? data.validators : [];
+      var quorum = validators.length > 0 ? Math.floor(2 * validators.length / 3) + 1 : 0;
+
+      document.getElementById('valCount').textContent   = validators.length;
+      document.getElementById('quorumCount').textContent = quorum || '—';
+
+      var tbody = document.getElementById('valBody');
+      if (!validators.length) {
+        tbody.innerHTML = '<tr><td colspan="4" class="tbl-empty">No validators found.</td></tr>';
+        C.setStatus('No validators registered.', 'warn');
+        return;
+      }
+
+      var rows = '';
+      validators.forEach(function(v, i) {
+        var addr   = v.address  || '—';
+        var pubKey = v.pub_key  || '—';
+        rows +=
+          '<tr>' +
+          '<td class="text-muted" style="font-size:12px">' + (i + 1) + '</td>' +
+          '<td>' +
+            '<a class="mono" href="/address?address=' + encodeURIComponent(pubKey) + '">' +
+              C.esc(addr) +
+            '</a>' +
+          '</td>' +
+          '<td class="mono" style="color:var(--muted);font-size:12px">' +
+            C.esc(C.short(pubKey, 32)) +
+          '</td>' +
+          '<td>' +
+            '<a href="/node?node=' + encodeURIComponent(pubKey) + '" class="pill-link" style="font-size:12px;padding:4px 10px">' +
+              '<i data-lucide="server"></i> Node' +
+            '</a>' +
+          '</td>' +
+          '</tr>';
+      });
+      tbody.innerHTML = rows;
+
+      C.setStatus(
+        validators.length + ' validator' + (validators.length !== 1 ? 's' : '') +
+        ' · quorum: ' + quorum,
+        'ok'
+      );
+      C.refreshIcons();
+    } catch (e) {
+      C.setStatus('Load failed: ' + e.message, 'err');
+    }
+  }
+
+  document.getElementById('refreshBtn').addEventListener('click', loadValidators);
+  loadValidators();
+})();