Add Entra diagrams to SC-900 describe-microsoft-entra unit

- Add product family diagram (1a-entra-product-family.png)
- Add products-work-together flow diagram (1a-entra-products-work-together.png)
- Update unit markdown with lightbox image references

Author: ceperezb

learn-pr/wwl-sci/explore-basic-services-identity-types/includes/1a-describe-microsoft-entra.md

@@ -22,6 +22,8 @@ The core products in the Microsoft Entra family include:
 - **Microsoft Entra Internet Access**: An identity-centric Secure Web Gateway (SWG) that protects access to internet and SaaS applications.
 - **Microsoft Entra Private Access**: Provides Zero Trust Network Access (ZTNA) to private apps and resources without requiring a traditional VPN.
 
+:::image type="content" source="../media/1a-entra-product-family.png" alt-text="Microsoft Entra product family organized into four categories: identity and access management, identity governance, network access, and verified identity." lightbox="../media/1a-entra-product-family.png":::
+
 ## How Microsoft Entra products work together
 
 The strength of the Microsoft Entra family lies in how its products integrate with each other. Consider a scenario where an employee joins your organization:
@@ -33,6 +35,8 @@ The strength of the Microsoft Entra family lies in how its products integrate wi
 
 This integrated approach reduces security gaps that occur when organizations use disconnected tools for identity and network access management.
 
+:::image type="content" source="../media/1a-entra-products-work-together.png" alt-text="Flow diagram showing how four Microsoft Entra products work together: Entra ID authenticates, Entra ID Governance provisions access, Entra Internet Access secures cloud connections, and Entra Private Access secures private apps." lightbox="../media/1a-entra-products-work-together.png":::
+
 > [!NOTE]
 > Each product in the Microsoft Entra family can be used independently, but they deliver the most value when used together as part of a comprehensive identity and access strategy.