[SDK-386] embedded card improvements

[franco-zalamena-iterable]

🔹 Jira Ticket(s) if any

• SDK-386

✏️ Description

Improvements to the Card Embedded View Image and buttons configurations.
NEW image scale type config option for the embedded view

The Card Embedded view currently had display issues for the buttons, with them showing up with a start padding that made them unaligned. To match the campaign preview they are now aligned to the left padding from the card itself.

The image from the card embedded now has an aspect ratio field that can be configured by the new image scale type field

closes #997

[sumeruchat]

• The UI/layout changes look reasonable, but the public IterableEmbeddedViewConfig constructor change introduces a source-compatibility regression for
existing Java consumers of the SDK. That makes the patch incorrect as a library change until compatibility is preserved.

Review comment:

• [P2] Preserve Java source compatibility for IterableEmbeddedViewConfig — /Users/sumeru.chatterjee/MyProjects/iterable-android-sdk/iterableapi-ui/src/main/
  java/com/iterable/iterableapi/ui/embedded/IterableEmbeddedViewConfig.kt:5-16
  If an app integrates this SDK from Java and already calls new IterableEmbeddedViewConfig(...), this change breaks compilation on upgrade because Kotlin
  default parameters do not create a shorter Java overload. Adding imageScaleType changes the only public constructor from 10 args to 11 args, so every
  existing Java call site now fails until it is updated manually.