feat: add active time window to countdown rules

UI: Active Window Start/End time inputs on countdown form.
Leave blank = runs any time. End before start = crosses midnight.
Scheduler: checks current time against window before starting timer;
supports cross-midnight windows (e.g. 9:00 AM to 4:00 AM next day).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/homebridge-plugin/homebridge-ui/public/index.html

@@ -394,10 +394,6 @@
       </div>
 
       <div id="dwm-countdown-fields" style="display:none">
-        <div class="form-group">
-          <label>Countdown Duration (minutes)</label>
-          <input type="number" id="dwm-countdown-mins" min="1" max="1440" placeholder="60" />
-        </div>
         <div class="form-group">
           <label>Condition</label>
           <select id="dwm-countdown-action">
@@ -405,6 +401,22 @@
             <option value="off_to_on">If device turns OFF → auto-ON after duration</option>
           </select>
         </div>
+        <div class="form-group">
+          <label>Countdown Duration (minutes)</label>
+          <input type="number" id="dwm-countdown-mins" min="1" max="1440" placeholder="60" />
+        </div>
+        <div class="flex-row">
+          <div class="form-group" style="flex:1">
+            <label>Active Window Start</label>
+            <input type="text" id="dwm-countdown-window-start" placeholder="e.g. 9:00 AM" />
+          </div>
+          <div class="form-group" style="flex:1">
+            <label>Active Window End</label>
+            <input type="text" id="dwm-countdown-window-end" placeholder="e.g. 4:00 AM" />
+            <div style="font-size:0.75rem;color:var(--muted);margin-top:3px">End before start = next day</div>
+          </div>
+        </div>
+        <div style="font-size:0.75rem;color:var(--muted);margin-bottom:8px">Leave window blank to run at any time.</div>
       </div>
 
       <div id="dwm-alwayson-info" style="display:none;margin-bottom:12px;padding:10px;background:rgba(48,209,88,.1);border:1px solid rgba(48,209,88,.3);border-radius:6px;font-size:0.82rem;color:#4ade80">

packages/homebridge-plugin/homebridge-ui/public/index.js

@@ -197,7 +197,10 @@ function dwmRuleSummary(r) {
   if (r.type === 'Countdown') {
     const mins = r.countdownTime ? Math.round(r.countdownTime / 60) : null;
     const cond = r.countdownAction === 'off_to_on' ? 'OFF→ON' : 'ON→OFF';
-    return mins ? `⏱ ${mins} min · ${cond}` : '—';
+    const win  = (r.windowStart >= 0 && r.windowEnd >= 0)
+      ? ` · ${secsToHHMM(r.windowStart)}–${secsToHHMM(r.windowEnd)}`
+      : (r.windowStart >= 0 ? ` · from ${secsToHHMM(r.windowStart)}` : '');
+    return mins ? `⏱ ${mins} min · ${cond}${win}` : '—';
   }
   const days = dayLabel(r.days);
   const devs = (r.targetDevices ?? []).map((td) => esc(td.name ?? td.host)).join(', ') || 'no targets';
@@ -444,6 +447,8 @@ function openDwmEdit(id) {
     document.getElementById('dwm-countdown-mins').value =
       r.countdownTime ? String(Math.round(r.countdownTime / 60)) : '';
     document.getElementById('dwm-countdown-action').value       = r.countdownAction ?? 'on_to_off';
+    document.getElementById('dwm-countdown-window-start').value = r.windowStart >= 0 ? secsToHHMM(r.windowStart) : '';
+    document.getElementById('dwm-countdown-window-end').value   = r.windowEnd   >= 0 ? secsToHHMM(r.windowEnd)   : '';
 
     _selectedDwmDays = new Set((r.days ?? []).map(Number));
 
@@ -478,6 +483,8 @@ function openDwmEdit(id) {
     document.getElementById('dwm-end-action').value   = '-1';
     document.getElementById('dwm-countdown-mins').value          = '';
     document.getElementById('dwm-countdown-action').value        = 'on_to_off';
+    document.getElementById('dwm-countdown-window-start').value  = '';
+    document.getElementById('dwm-countdown-window-end').value    = '';
     document.getElementById('dwm-trigger-src').value       = '';
     document.getElementById('dwm-trigger-event').value  = 'any';
     document.getElementById('dwm-trigger-action').value = 'on';
@@ -609,6 +616,10 @@ document.getElementById('dwm-form-save-btn').addEventListener('click', async ()
     if (!mins || mins < 1) { showModalError('Enter countdown duration in minutes'); return; }
     rule.countdownTime    = mins * 60;
     rule.countdownAction  = document.getElementById('dwm-countdown-action').value;
+    const winStart = hhmmToSecs(document.getElementById('dwm-countdown-window-start').value);
+    const winEnd   = hhmmToSecs(document.getElementById('dwm-countdown-window-end').value);
+    rule.windowStart = winStart >= 0 ? winStart : -1;
+    rule.windowEnd   = winEnd   >= 0 ? winEnd   : -1;
   } else {
     const startType   = document.getElementById('dwm-start-type').value;
     const startOffset = parseInt(document.getElementById('dwm-start-offset').value ?? '0', 10) || 0;

packages/homebridge-plugin/lib/scheduler.js

@@ -587,16 +587,30 @@ class DwmScheduler {
           }
         }
 
-        // ── Countdown — fire only when state matches configured condition ──
+        // ── Countdown — fire only when state matches condition and within window ──
         if (countdownDevMap.has(key)) {
           const prevState = this._countdownStates.get(key);
           this._countdownStates.set(key, isOn);
           if (prevState !== undefined && prevState !== isOn) {
+            const nowSecs = secondsFromMidnight(new Date());
             for (const { rule, td } of countdownDevMap.get(key)) {
               const condition  = rule.countdownAction ?? 'on_to_off';
               const triggered  = condition === 'on_to_off' ? isOn : !isOn;
               if (!triggered) continue;  // state doesn't match this rule's condition
 
+              // Check active window (if defined)
+              const winStart = Number(rule.windowStart ?? -1);
+              const winEnd   = Number(rule.windowEnd   ?? -1);
+              if (winStart >= 0 && winEnd >= 0) {
+                const crossesMidnight = winEnd < winStart;
+                const inWindow = crossesMidnight
+                  ? (nowSecs >= winStart || nowSecs <= winEnd)
+                  : (nowSecs >= winStart && nowSecs <= winEnd);
+                if (!inWindow) continue;  // outside active window
+              } else if (winStart >= 0) {
+                if (nowSecs < winStart) continue;
+              }
+
               const timerKey  = `${key}-${rule.id}`;
               // Cancel any pending timer for this device+rule
               const existing  = this._countdownTimers.get(timerKey);