Add support for remotely loaded images in RMF

[catalinradoiu]

Task/Issue URL: https://app.asana.com/1/137249556945/project/1211724162604201/task/1212745281144616?focus=true

Description

This PR adds support for loading remote images in the RMF components. It implements:

• Updated MessageCta to handle image URLs and display them using Glide
• Created a RemoteMessageImagePrefetcher to preload remote images for better performance
• The image is stored in a local file that is deleted after the message is dismissed
• Updated the RemoteMessage model to include imageUrl field in various content types
• Modified UI layouts to accommodate remote images with proper transitions

Steps to test this PR

Remote Image Loading

• Verify that remote images load correctly in RMF components (modal and NTP) by checking the scenarios from this task: https://app.asana.com/1/137249556945/project/1211724162604201/task/1212790148571056?focus=true

UI changes

NTP	Modal

The image that was loaded is taken from https://staticcdn.duckduckgo.com/remotemessaging/illustrations/image.png

---

Note

Adds remote image loading to RMF with prefetching and local caching for smoother rendering.

• Introduces RemoteMessageImageStore (Glide-backed) to prefetch, persist, supply, and clear message images; wired via DI and repository (getRemoteMessageImageFile) and cleared on dismiss
• Extends RemoteMessage.Content models and JSON mappers with optional imageUrl; maps through to UI via asMessage(..., localImageFilePath)
• Updates MessageCta to render imageUrl or local file with Glide (fallback to drawable/animation), plus new ImageViews and barriers in view_remote_message_cta.xml, view_promo_message_cta.xml
• Propagates image file path through RemoteMessageViewModel and NewTabLegacyPageViewModel/View to MessageCta
• Adds remote image handling to Cards List modal view and layout
• Adds Glide dependency to modules and comprehensive unit tests

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[catalinradoiu]

• Send pixel events for the RMF remote image load success/ failure #7496
• Add support for remotely loaded images in RMF #7445 👈 (View in Graphite)
• develop

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[cmonfortep]

LGTM

[cmonfortep]

ditto re sizes

[cmonfortep]

LGTM