Rebrand app to "Wenza" (display name + user-facing copy)

Renames the user-facing app to Wenza without changing identity:
- CFBundleDisplayName → "Wenza" (app) and "Wenza Widgets" (widget extension).
- Calendar/Health permission prompts now reference Wenza.
- In-app copy updated: sidebar title, Auth + Onboarding screens, Settings
  about/help rows, feedback email subject, tutorial text, widget description.

Bundle identifier, App Group, UserDefaults storage keys, team ID, and the
internal Xcode target/project names are intentionally unchanged, so this stays
the same App Store app with no user data loss. App Store listing name must be
changed separately in App Store Connect.

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

KisaniCalWidgets/Info.plist

@@ -5,7 +5,7 @@
 	<key>CFBundleDevelopmentRegion</key>
 	<string>$(DEVELOPMENT_LANGUAGE)</string>
 	<key>CFBundleDisplayName</key>
-	<string>Kisani Cal Widgets</string>
+	<string>Wenza Widgets</string>
 	<key>CFBundleExecutable</key>
 	<string>$(EXECUTABLE_NAME)</string>
 	<key>CFBundleIdentifier</key>

KisaniCalWidgets/KisaniCalWidgets.swift

@@ -53,7 +53,7 @@ enum ProgressDotMode: String, AppEnum {
 
 struct ProgressDotConfigIntent: WidgetConfigurationIntent {
     static var title: LocalizedStringResource = "Progress Dots"
-    static var description = IntentDescription("Track day, week, month, or a KisaniCal event.")
+    static var description = IntentDescription("Track day, week, month, or a Wenza event.")
 
     @Parameter(title: "Mode", default: .month)
     var mode: ProgressDotMode