Time-travel map: filter nodes by replay timestamp

When scrubbing to a past time, only nodes that had advertised before
that time appear on the map. Nodes that hadn't been seen yet are
hidden.

- Added 'before' param to /api/nodes (filters first_seen <= before)
- loadNodes(beforeTs) accepts optional timestamp filter
- clearNodeMarkers() removes all markers and data
- vcrReplayFromTs clears and reloads nodes for replay time
- vcrResumeLive reloads all nodes (no filter)

public/live.js

@@ -92,6 +92,9 @@
     VCR.dragPct = null;
     VCR.scrubTs = null;
     vcrSetMode('LIVE');
+    // Reload all nodes (no time filter)
+    clearNodeMarkers();
+    loadNodes();
     const prompt = document.getElementById('vcrPrompt');
     if (prompt) prompt.classList.add('hidden');
   }
@@ -115,6 +118,11 @@
     const fetchTo = new Date(targetTs + 300000).toISOString(); // 5 min window
     stopReplay();
     vcrSetMode('REPLAY');
+
+    // Reload map nodes to match the replay time
+    clearNodeMarkers();
+    loadNodes(targetTs);
+
     fetch(`/api/packets?limit=200&grouped=false&since=${encodeURIComponent(fetchFrom)}&until=${encodeURIComponent(fetchTo)}`)
       .then(r => r.json())
       .then(data => {
@@ -818,9 +826,12 @@
     }, 2000);
   }
 
-  async function loadNodes() {
+  async function loadNodes(beforeTs) {
     try {
-      const resp = await fetch('/api/nodes?limit=500');
+      const url = beforeTs
+        ? `/api/nodes?limit=500&before=${encodeURIComponent(new Date(beforeTs).toISOString())}`
+        : '/api/nodes?limit=500';
+      const resp = await fetch(url);
       const nodes = await resp.json();
       const list = Array.isArray(nodes) ? nodes : (nodes.nodes || []);
       list.forEach(n => {
@@ -833,6 +844,14 @@
     } catch (e) { console.error('Failed to load nodes:', e); }
   }
 
+  function clearNodeMarkers() {
+    for (const [key, marker] of Object.entries(nodeMarkers)) {
+      if (map) map.removeLayer(marker);
+    }
+    nodeMarkers = {};
+    nodeData = {};
+  }
+
   function addNodeMarker(n) {
     if (nodeMarkers[n.public_key]) return nodeMarkers[n.public_key];
     const color = ROLE_COLORS[n.role] || ROLE_COLORS.unknown;

server.js

@@ -455,13 +455,14 @@ app.post('/api/packets', (req, res) => {
 });
 
 app.get('/api/nodes', (req, res) => {
-  const { limit = 50, offset = 0, role, region, lastHeard, sortBy = 'lastSeen', search } = req.query;
+  const { limit = 50, offset = 0, role, region, lastHeard, sortBy = 'lastSeen', search, before } = req.query;
 
   let where = [];
   let params = {};
 
   if (role) { where.push('role = @role'); params.role = role; }
   if (search) { where.push('name LIKE @search'); params.search = `%${search}%`; }
+  if (before) { where.push('first_seen <= @before'); params.before = before; }
   if (lastHeard) {
     const durations = { '1h': 3600000, '6h': 21600000, '24h': 86400000, '7d': 604800000, '30d': 2592000000 };
     const ms = durations[lastHeard];