Widgets: align every widget to the exact logo palette (KC-19)

WidgetTheme now uses the true brand colors — accent RGB(232,98,42) on
the logo's dark RGB(26,29,34) — replacing a near-miss orange on slate.
Bars countdown, My Tasks, and Day Progress inherit it; Task Live
Activity drops its hardcoded accent/black tint for the theme; lock
screen rings tint brand orange.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

KisaniCalWidgets/TaskLiveActivity.swift

@@ -4,7 +4,7 @@ import SwiftUI
 
 @available(iOS 16.1, *)
 struct TaskLiveActivity: Widget {
-    private let accent = Color(red: 0.93, green: 0.42, blue: 0.20) // brand orange
+    private let accent = WidgetTheme.accent // brand orange
 
     var body: some WidgetConfiguration {
         ActivityConfiguration(for: TaskActivityAttributes.self) { context in
@@ -35,7 +35,7 @@ struct TaskLiveActivity: Widget {
             }
             .padding(.horizontal, 16)
             .padding(.vertical, 12)
-            .activityBackgroundTint(Color.black.opacity(0.55))
+            .activityBackgroundTint(WidgetTheme.background.opacity(0.9))
             .activitySystemActionForegroundColor(.white)
 
         } dynamicIsland: { context in