Widgets: bars countdown widget + unified slate/orange theme (KC-15)

- New EventBarsWidget ("Event Countdown (Bars)") using BarGrid + EventBarsView,
  with a fine "X hr, Y min left" label; registered in the bundle.
- Re-themed every home-screen widget to the shared WidgetTheme (dark slate
  background + brand orange): Day Progress, Tasks Done Today, Event Countdown
  (dots), My Tasks. Lock-screen widgets keep .thinMaterial (system-tinted).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

KisaniCalWidgets/EventCountdownWidget.swift

@@ -151,6 +151,18 @@ struct EventEntry: TimelineEntry {
         return max(0, d)
     }
 
+    /// Granular countdown for the bars widget: days → hr → min as it nears.
+    var fineTimeLeft: String {
+        if target <= date { return "Today" }
+        let secs = target.timeIntervalSince(date)
+        let days = Int(secs / 86400)
+        let hrs  = Int(secs.truncatingRemainder(dividingBy: 86400) / 3600)
+        let mins = Int(secs.truncatingRemainder(dividingBy: 3600) / 60)
+        if days >= 1 { return hrs > 0 ? "\(days)d, \(hrs) hr left" : "\(days) day\(days == 1 ? "" : "s") left" }
+        if hrs  >= 1 { return "\(hrs) hr, \(mins) min left" }
+        return "\(mins) min left"
+    }
+
     /// Countdown from the current date. Tapping the label cycles the unit:
     /// days → weeks → time remaining.
     var timeLeftLabel: String {
@@ -254,3 +266,18 @@ struct EventCountdownWidget: Widget {
         .supportedFamilies([.systemMedium, .systemSmall])
     }
 }
+
+// MARK: - Event Countdown (Bars)
+
+struct EventBarsWidget: Widget {
+    let kind = "KisaniEventBars"
+
+    var body: some WidgetConfiguration {
+        AppIntentConfiguration(kind: kind, intent: EventConfigIntent.self, provider: EventProvider()) { entry in
+            EventBarsView(entry: entry)
+        }
+        .configurationDisplayName("Event Countdown (Bars)")
+        .description("Count down to an event with a bar meter.")
+        .supportedFamilies([.systemMedium])
+    }
+}