Add banner upload functionality to the shop home screen

[AleksandarBoljanovic]

What is the goal?

• Add the functionality to upload a banner for the shop's home page to the integration-core, and ensure this new configuration can be received via the configuration webhook sent by the merchant portal.

References

• Issue: LIS-111

How is it being implemented?

• Added new Checkout API controller (BannerCheckoutController) with getBannerForLocation endpoint, request and response - used by the storefront to fetch the banner to render for a given country/display location
• Registered new Configuration Webhook topics (get-banner-settings, save-banner-settings)
• Added the BannerSettings domain context: Banner and BannerSettings models, BannerSettings entity with EntityConfiguration, BannerSettingsRepositoryInterface + repository, and BannerSettingsService orchestrating fetch/save/delete and display-location-aware image updates
• Added new integration interface (BannerServiceInterface) as the platform extension point - exposes display locations, image upload/delete, and country lookup so each e-commerce platform supplies its own implementation
• Added a BANNER capability to Capability and surfaced it via StoreIntegrationService so platforms can advertise banner support
• Hooked into connection lifecycle: ConnectionService triggers banner-settings provisioning on connect, DisconnectService cleans up persisted settings and uploaded images on disconnect (with an error log if image deletion on the integration side fails)
• Wired everything in BootstrapComponent (repository, service, controllers, webhook handlers)
• Added unit tests

How is it tested?

• Unit tests