SDK-6049: Fix per-page deep links for auto and manual carousel templates - #62

Bug

In pt_carousel and pt_manual_carousel, tapping any page always opened pt_dl1 regardless of which page was visible. Two separate issues caused this.

• Issue 1 - pt_dl2 and pt_dl3 were never read

CarouselProperties only declared pt_dl1, so the decoder silently dropped the other two links. A single actionUrl derived from pt_dl1 was then assigned to every carousel item at construction time.

• Issue 2 - async race condition scrambled page order

Image validation calls are async. Results were appended to itemViews as they arrived, meaning the page at index 0 could end up being pt_img2 if it loaded faster than pt_img1, giving it the wrong deep link even if the links had been wired up correctly.

Changes

• Added pt_dl2 and pt_dl3 to CarouselProperties
• Each image slot in imageUrls now carries its own resolved deep link as a tuple field, paired at build time before any async work starts
• Replaced itemViews.append inside async callbacks with a [Int: CTCaptionedImageView] dictionary keyed by index. After all callbacks complete, dispatchGroup.notify assembles itemViews in correct slot order using compactMap, skipping any images that failed to load
• Extracted resolveDeeplink(_:fallback:) as a private method. If pt_dl2 or pt_dl3 is absent, it falls back to pt_dl1. If pt_dl1 is also absent, tapping fires performNotificationDefaultAction