🎨 Palette: [UX improvement] Add confirmation dialog for delete payment action

[shadowcoder8]

💡 What: Added a native browser confirm() dialog and explicit alert() success/failure feedback to the deletePayment function.

🎯 Why: To prevent accidental data loss and provide clear visual feedback to the user, aligning this destructive action with other similar functions across the application.

📸 Before/After: Before, the action executed immediately without warning. After, a confirmation dialog appears first, followed by an alert upon success or failure.

♿ Accessibility: This also improves accessibility by explicitly warning screen reader users of a destructive action before it completes.

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PR created automatically by Jules for task 12360191050182071157 started by @shadowcoder8

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