perf: use Map for O(1) pubKey lookup in ADVERT upsert handler

Replace _allNodes.find() (O(n) per advert) with a Map built once per
WS batch. With 2K+ nodes and multiple adverts per batch, this avoids
repeated linear scans in a hot path.

public/index.html

@@ -22,9 +22,9 @@
   <meta name="twitter:title" content="CoreScope">
   <meta name="twitter:description" content="Real-time MeshCore LoRa mesh network analyzer — live packet visualization, node tracking, channel decryption, and route analysis.">
   <meta name="twitter:image" content="https://raw.githubusercontent.com/Kpa-clawbot/corescope/master/public/og-image.png">
-  <link rel="stylesheet" href="style.css?v=1775062162">
-  <link rel="stylesheet" href="home.css?v=1775062162">
-  <link rel="stylesheet" href="live.css?v=1775062162">
+  <link rel="stylesheet" href="style.css?v=1775092976">
+  <link rel="stylesheet" href="home.css?v=1775092976">
+  <link rel="stylesheet" href="live.css?v=1775092976">
   <link rel="stylesheet" href="https://unpkg.com/leaflet@1.9.4/dist/leaflet.css"
     integrity="sha256-p4NxAoJBhIIN+hmNHrzRCf9tD/miZyoHS5obTRR9BMY="
     crossorigin="anonymous">
@@ -85,30 +85,30 @@
   <main id="app" role="main"></main>
 
   <script src="vendor/qrcode.js"></script>
-  <script src="roles.js?v=1775062162"></script>
-  <script src="customize.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="region-filter.js?v=1775062162"></script>
-  <script src="hop-resolver.js?v=1775062162"></script>
-  <script src="hop-display.js?v=1775062162"></script>
-  <script src="app.js?v=1775062162"></script>
-  <script src="home.js?v=1775062162"></script>
-  <script src="packet-filter.js?v=1775062162"></script>
-  <script src="packets.js?v=1775062162"></script>
-  <script src="geo-filter-overlay.js?v=1775062162"></script>
-  <script src="map.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="channels.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="nodes.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="traces.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="analytics.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="audio.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="audio-v1-constellation.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="audio-v2-constellation.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="audio-lab.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="live.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="observers.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="observer-detail.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="compare.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="node-analytics.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
-  <script src="perf.js?v=1775062162" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="roles.js?v=1775092976"></script>
+  <script src="customize.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="region-filter.js?v=1775092976"></script>
+  <script src="hop-resolver.js?v=1775092976"></script>
+  <script src="hop-display.js?v=1775092976"></script>
+  <script src="app.js?v=1775092976"></script>
+  <script src="home.js?v=1775092976"></script>
+  <script src="packet-filter.js?v=1775092976"></script>
+  <script src="packets.js?v=1775092976"></script>
+  <script src="geo-filter-overlay.js?v=1775092976"></script>
+  <script src="map.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="channels.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="nodes.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="traces.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="analytics.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="audio.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="audio-v1-constellation.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="audio-v2-constellation.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="audio-lab.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="live.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="observers.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="observer-detail.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="compare.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="node-analytics.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
+  <script src="perf.js?v=1775092976" onerror="console.error('Failed to load:', this.src)"></script>
 </body>
 </html>

public/nodes.js

@@ -228,11 +228,45 @@
     loadNodes();
     // Auto-refresh when ADVERT packets arrive via WebSocket (fixes #131)
     wsHandler = debouncedOnWS(function (msgs) {
-      if (msgs.some(isAdvertMessage)) {
-        _allNodes = null;
+      const advertMsgs = msgs.filter(isAdvertMessage);
+      if (!advertMsgs.length) return;
+
+      if (!_allNodes) {
         invalidateApiCache('/nodes');
         loadNodes(true);
+        return;
       }
+
+      // Build a Map for O(1) lookup instead of O(n) .find() per advert
+      var nodesByKey = new Map();
+      for (var i = 0; i < _allNodes.length; i++) {
+        if (_allNodes[i].public_key) nodesByKey.set(_allNodes[i].public_key, _allNodes[i]);
+      }
+
+      let needReload = false;
+      for (const m of advertMsgs) {
+        const payload = m.data && m.data.decoded && m.data.decoded.payload;
+        const pubKey = payload && (payload.pubKey || payload.public_key);
+        if (!pubKey) { needReload = true; break; }
+
+        const existing = nodesByKey.get(pubKey);
+        if (existing) {
+          if (payload.name) existing.name = payload.name;
+          if (payload.lat != null) existing.lat = payload.lat;
+          if (payload.lon != null) existing.lon = payload.lon;
+          const ts = m.data.packet && (m.data.packet.timestamp || m.data.packet.first_seen);
+          if (ts) existing.last_seen = ts;
+        } else {
+          needReload = true;
+          break;
+        }
+      }
+
+      if (needReload) {
+        _allNodes = null;
+        invalidateApiCache('/nodes');
+      }
+      loadNodes(true);
     }, 5000);
   }
 
@@ -929,4 +963,6 @@
 
   // Test hooks
   window._nodesIsAdvertMessage = isAdvertMessage;
+  window._nodesGetAllNodes = function() { return _allNodes; };
+  window._nodesSetAllNodes = function(n) { _allNodes = n; };
 })();

test-frontend-helpers.js

@@ -1181,6 +1181,61 @@ console.log('\n=== nodes.js: WS handler runtime behavior ===');
     assert.ok(env.getApiCalls() > 0, 'api called because _allNodes was reset to null');
   });
 
+  test('ADVERT for known node upserts in-place without API fetch', () => {
+    const env = makeNodesWsSandbox();
+    // Pre-populate _allNodes with a known node
+    assert.ok(typeof env.ctx.window._nodesSetAllNodes === 'function', '_nodesSetAllNodes must be exposed');
+    env.ctx.window._nodesSetAllNodes([
+      { public_key: 'aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899', name: 'OldName', role: 'repeater', lat: null, lon: null, last_seen: '2024-01-01T00:00:00Z' }
+    ]);
+    env.resetCounters();
+
+    env.sendWS({
+      type: 'packet',
+      data: {
+        packet: { payload_type: 4, timestamp: '2024-06-01T12:00:00Z' },
+        decoded: {
+          header: { payloadTypeName: 'ADVERT' },
+          payload: { type: 'ADVERT', pubKey: 'aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899', name: 'NewName', lat: 50.85, lon: 4.35 }
+        }
+      }
+    });
+    env.fireTimers();
+
+    assert.strictEqual(env.getApiCalls(), 0, 'known node upsert must NOT trigger API fetch');
+    assert.strictEqual(env.getInvalidated().length, 0, 'no cache invalidation for known node upsert');
+    const nodes = env.ctx.window._nodesGetAllNodes();
+    assert.ok(nodes, '_nodesGetAllNodes must be exposed');
+    assert.strictEqual(nodes[0].name, 'NewName', 'name must be updated in place');
+    assert.strictEqual(nodes[0].lat, 50.85, 'lat must be updated in place');
+    assert.strictEqual(nodes[0].lon, 4.35, 'lon must be updated in place');
+    assert.strictEqual(nodes[0].last_seen, '2024-06-01T12:00:00Z', 'last_seen must be updated from packet timestamp');
+  });
+
+  test('ADVERT for unknown node falls back to full reload', () => {
+    const env = makeNodesWsSandbox();
+    env.ctx.window._nodesSetAllNodes([
+      { public_key: 'aabbccddeeff00112233445566778899aabbccddeeff00112233445566778899', name: 'ExistingNode', role: 'repeater' }
+    ]);
+    env.resetCounters();
+
+    // Send ADVERT from a pubKey NOT in _allNodes
+    env.sendWS({
+      type: 'packet',
+      data: {
+        packet: { payload_type: 4 },
+        decoded: {
+          header: { payloadTypeName: 'ADVERT' },
+          payload: { type: 'ADVERT', pubKey: 'ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff', name: 'BrandNewNode' }
+        }
+      }
+    });
+    env.fireTimers();
+
+    assert.ok(env.getApiCalls() > 0, 'unknown node must trigger full reload');
+    assert.ok(env.getInvalidated().includes('/nodes'), 'cache must be invalidated for unknown node');
+  });
+
   test('scroll position and selection preserved during WS-triggered refresh', () => {
     const env = makeNodesWsSandbox();
     // Simulate scrolled panel state — WS handler should not touch scroll or rebuild panel