v0.5.0 - Wake-on-LAN + connectivity history

wol.py:
- build_magic_packet(): standard 6x0xFF + 16x MAC layout
- send_local_broadcast(): direct from container (ports 9 + 7 for safety)
- send_via_peer(): preferred path; SSHes to the OTHER Spark and runs a Python one-liner there so the packet originates on the target's LAN segment (most reliable)
- MAC validation + normalization

connectivity.py:
- /data/connectivity.json persistence (thread-safe, atomic rename)
- Stores per-Spark current state + last_change timestamp + rolling 200-event log
- Records up/down transitions; computes down_seconds / up_seconds durations
- MAC cache populated lazily during hardware probes

hardware.py:
- Probe now reads MAC via /sys/class/net/<default-route-iface>/address
- After each probe, record_state() emits a transition event if state changed
- record_mac() caches the address so WoL works when the Spark next goes down

Endpoints:
- GET /api/connectivity: macs, current state, last_change, events[]
- POST /api/spark/{name}/wake: tries via-peer first, falls back to direct broadcast

UI:
- Unreachable hardware card shows the cached MAC + 'Wake (WoL)' button (only if MAC known)
- New 'Connectivity log' button opens a modal with per-Spark transition history (last 25 each), including duration of each prior up/down period
- pollHardware also pulls /api/connectivity so WoL buttons appear without an extra fetch

Package: bump 0.5.0:0; main.ts sets CONNECTIVITY_LOG=/data/connectivity.json

image/app/static/app.js

@@ -121,10 +121,69 @@ function bar(usedPct, warn) {
 async function pollHardware() {
   try {
     state.hardware = await fetchJSON('/api/hardware');
+    try { state.connectivity = await fetchJSON('/api/connectivity'); } catch {}
     renderHardware();
   } catch (e) { console.warn('hardware poll failed', e); }
 }
 
+function fmtDuration(sec) {
+  if (sec == null) return '';
+  if (sec < 60) return `${Math.round(sec)}s`;
+  if (sec < 3600) return `${Math.round(sec / 60)}m`;
+  if (sec < 86400) {
+    const h = Math.floor(sec / 3600);
+    const m = Math.round((sec % 3600) / 60);
+    return m ? `${h}h ${m}m` : `${h}h`;
+  }
+  const d = Math.floor(sec / 86400);
+  const h = Math.round((sec % 86400) / 3600);
+  return h ? `${d}d ${h}h` : `${d}d`;
+}
+
+function openConnectivityDialog() {
+  const dlg = el('#connectivity-dialog');
+  const content = el('#connectivity-content');
+  const c = state.connectivity || {};
+  const events = c.events || [];
+  if (events.length === 0) {
+    content.innerHTML = '<div class="muted small">No transitions recorded yet. Once a Spark goes down and comes back, you\'ll see entries here.</div>';
+    dlg.showModal();
+    return;
+  }
+  const bySpark = {};
+  for (const e of events) {
+    (bySpark[e.spark] = bySpark[e.spark] || []).push(e);
+  }
+  const html = Object.entries(bySpark).map(([spark, evs]) => {
+    const downs = evs.filter(e => e.transition === 'down').length;
+    const mac = c.macs?.[spark];
+    return `
+      <div class="conn-spark">
+        <h4>${escapeHtml(spark)}${mac ? ` <span class="muted small">${escapeHtml(mac)}</span>` : ''}</h4>
+        <div class="conn-summary">${evs.length} transition${evs.length===1?'':'s'} · ${downs} down event${downs===1?'':'s'} in window</div>
+        ${evs.slice(-25).reverse().map(e => `
+          <div class="conn-event ${e.transition}">
+            <span class="when">${escapeHtml(e.at.replace('T', ' ').replace('Z', ''))}</span>
+            <span class="what">${e.transition === 'up' ? '↑ came back online' : '↓ dropped offline'}</span>
+            <span class="dur">${e.down_seconds != null ? `was down ${fmtDuration(e.down_seconds)}` : ''}${e.up_seconds != null ? `was up ${fmtDuration(e.up_seconds)}` : ''}</span>
+          </div>
+        `).join('')}
+      </div>
+    `;
+  }).join('');
+  content.innerHTML = html;
+  dlg.showModal();
+}
+
+async function wakeSpark(name) {
+  try {
+    const r = await fetchJSON(`/api/spark/${name}/wake`, { method: 'POST' });
+    alert(`Wake-on-LAN sent to ${name} (MAC ${r.mac}, via ${r.delivered_via}). Give it ~30 seconds to wake; the card will go green when it comes back.`);
+  } catch (e) {
+    alert(`Wake failed: ${e.message}`);
+  }
+}
+
 function renderHardware() {
   const panel = el('#hardware-panel');
   const grid = el('#hardware-grid');
@@ -138,14 +197,23 @@ function renderHardware() {
     const card = document.createElement('div');
     if (!s.reachable) {
       card.className = 'hw-card unreachable';
+      const mac = state.connectivity?.macs?.[key];
+      const wolRow = mac
+        ? `<div class="wol-row">
+             <span class="mac-display">${escapeHtml(mac)}</span>
+             <span class="spacer"></span>
+             <button class="btn" data-wake="${escapeHtml(key)}">Wake (WoL)</button>
+           </div>`
+        : `<div class="muted small">MAC not yet known — once it's been up once with this dashboard installed, "Wake" will appear here.</div>`;
       card.innerHTML = `
         <div class="head">
           <span class="name">${escapeHtml(key)}</span>
           <span class="meta">unreachable</span>
         </div>
         <div class="muted small">${escapeHtml(s.host || '')} — ${escapeHtml(s.error || 'no response')}</div>
+        ${wolRow}
         <div class="muted small" style="line-height:1.5">
-          Spark Control can't restart a Spark that won't answer SSH. Steps to try:
+          If Wake-on-LAN doesn't bring it back, manual steps:
           <ol style="margin: 6px 0 0 18px; padding: 0;">
             <li>Verify it's powered on (check the front LED).</li>
             <li>Ping it from another LAN device.</li>
@@ -1307,6 +1375,13 @@ async function init() {
   el('#nim-cancel').addEventListener('click', () => el('#nim-dialog').close());
   el('#nim-form').addEventListener('submit', submitNim);
   el('#nim-prog-close').addEventListener('click', () => el('#nim-progress-dialog').close());
+  el('#open-connectivity').addEventListener('click', openConnectivityDialog);
+  el('#connectivity-close').addEventListener('click', () => el('#connectivity-dialog').close());
+  // Wake-on-LAN buttons live on unreachable hardware cards; delegate.
+  el('#hardware-grid').addEventListener('click', (e) => {
+    const btn = e.target.closest('[data-wake]');
+    if (btn) wakeSpark(btn.dataset.wake);
+  });
   setupCatalogDialog();
   setupAdvancedDialog();
   // Open WebUI link from /api/config