🎨 Palette: [AppDiagnostics] Add accessible feedback to Copy Report button

[emkey1]

💡 What: Wrapped the copiedReport state toggle in withAnimation, added haptic feedback via UINotificationFeedbackGenerator, broadcasted a screen reader announcement via UIAccessibility.post, and added an accessibilityHint to the "Copy Report" button in AppDiagnosticsView.swift.
🎯 Why: Transient UI actions like "Copying" offer no non-visual feedback for VoiceOver users and visual transitions appear abruptly without animation.
📸 Before/After: Visual text previously snapped; now transitions smoothly.
♿ Accessibility: Ensures VoiceOver announces the copied state and clarifies the button's action through hints.

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PR created automatically by Jules for task 8832575408553099700 started by @emkey1

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