Add PaywallListener convenience prop to PaywallView components

[rickvdl]

Summary

• Adds PaywallListener and PurchaseResumable interfaces matching the Capacitor SDK definitions
• Adds listener prop to PaywallView and PaywallFooterContainerView as a convenience alternative to passing individual callback props
• Individual callback props take precedence over listener callbacks when both are provided
• No native changes required — purely TypeScript-level convenience

Related PRs

• Based on: Add custom PurchaseLogic support to PaywallView component #1607 (PurchaseLogic support for PaywallView)
• Capacitor equivalent: [SDK-4264] Add PaywallListener and PurchaseLogic to purchases-capacitor-ui purchases-capacitor#688

Test plan

• Verify TypeScript compiles without errors
• Verify API testers pass type-checking
• Test listener prop on PaywallView — purchase/restore callbacks fire
• Test that individual callback props override listener callbacks
• Test that omitting listener doesn't regress existing behavior (existing "Go to Paywall Screen" works as before)

[rickvdl]

Replaces #1632 which was accidentally closed.

[tonidero]

🚢