[docs] Update documentation to reflect .aab fast deployment support (#10963)

## Summary

Updates documentation across multiple files to reflect that fast deployment now works with `.aab` files (Android App Bundles), as implemented in PR #8990.

Context: #9455 (comment)

## Changes

- **`Documentation/guides/AndroidAssetPacks.md`**: Removed incorrect statement that setting `AndroidPackageFormat` to `aab` disables fast deployment. Added note explaining `.aab` is supported but slower than `.apk` due to `bundletool` processing.
- **`Documentation/docs-mobile/building-apps/build-process.md`**: Updated Fast Deployment section to explicitly state support for both `.apk` and `.aab` package formats, with caveat about performance difference.
- **`Documentation/docs-mobile/building-apps/build-properties.md`**: Updated `AndroidFastDeploymentType`, `EmbedAssembliesIntoApk`, and `AndroidPackageFormats` property descriptions to reflect `.aab` support. Softened the recommendation against using `aab` for debugging.
- **`Documentation/docs-mobile/messages/xa0119.md`**: Removed the "App Bundles" bullet from the list of non-ideal Debug configuration settings, since using `.aab` in Debug is now a valid scenario (e.g., for testing asset packs) with fast deployment support.

Co-authored-by: Jonathan Peppers <jonathan.peppers@microsoft.com>

Author: Copilot

Documentation/docs-mobile/building-apps/build-process.md

@@ -50,8 +50,12 @@ Only the updated assemblies are resynchronized to the target device.
 > [!WARNING]
 > Fast deployment is known to fail on devices which block `run-as`, which often includes devices older than Android 5.0.
 
-Fast deployment is enabled by default, and may be disabled in Debug builds
+Fast deployment is supported for both `.apk` and `.aab` package formats.
+It is enabled by default, and may be disabled in Debug builds
 by setting the `$(EmbedAssembliesIntoApk)` property to `True`.
+Note that using `.aab` with fast deployment will be slower than `.apk`
+because the `.aab` file must be processed through `bundletool` for
+packaging and installation.
 
 The [Enhanced Fast Deployment](build-properties.md#androidfastdeploymenttype) mode can
 be used in conjunction with this feature to speed up deployments even further.

Documentation/docs-mobile/building-apps/build-properties.md

@@ -553,9 +553,9 @@ of values to control what types can be deployed to the
 on the target device
 when the [`$(EmbedAssembliesIntoApk)`](#embedassembliesintoapk) MSBuild
 property is `False`. If a resource is fast deployed, it is *not*
-embedded into the generated `.apk`, which can speed up deployment
+embedded into the generated `.apk` or `.aab`, which can speed up deployment
 times. (The more that is fast deployed, then the less frequently
-the `.apk` needs to be rebuilt, and the install process can be
+the package needs to be rebuilt, and the install process can be
 faster.) Valid values include:
 
 - `Assemblies`: Deploy application assemblies.
@@ -1042,7 +1042,8 @@ being generated. Setting `AndroidPackageFormats` to either `aab`
 or `apk` will generate only one file.
 
 The default value is `aab;apk` for `Release` builds only.
-It is recommended that you continue to use just `apk` for debugging.
+Using `apk` for debugging is faster, but `aab` is also supported
+with fast deployment if needed (for example, when testing asset packs).
 
 ## AndroidPackageNamingPolicy
 
@@ -1639,7 +1640,7 @@ Deployment doesn't support the target device.
 When this property is `False`, then the
 [`$(AndroidFastDeploymentType)`](#androidfastdeploymenttype)
 MSBuild property also controls what
-will be embedded into the `.apk`, which can impact deployment and
+will be embedded into the `.apk` or `.aab`, which can impact deployment and
 rebuild times.
 
 ## EnableDiagnostics

Documentation/docs-mobile/messages/xa0119.md

@@ -27,8 +27,6 @@ Remove the following options from `Debug` configurations:
   * `<EnableProguard>True</EnableProguard>`
   * `<AndroidLinkTool>proguard</AndroidLinkTool>`
   * `<AndroidLinkTool>r8</AndroidLinkTool>`
-* App Bundles
-  * `<AndroidPackageFormat>aab</AndroidPackageFormat>`
 
 Remove the following from `Release` configurations:
 

Documentation/guides/AndroidAssetPacks.md

@@ -125,9 +125,12 @@ away during the Release build.
 In order to test your asset packs in the `Debug` configuration, you will need to
 make some changes to your `.csproj`. Firstly we need to change the
 `$(AndroidPackageFormat)` to `aab`. It will be `aab` by default for `Release` builds,
-but will default to `apk` for `Debug` builds. Setting the `AndroidPackageFormat` to `aab`
-will disable fast deployment, so it is advised that you only do this when you need to test
-your `AssetPacks`.
+but will default to `apk` for `Debug` builds.
+
+> [!NOTE]
+> Fast deployment is supported with `.aab` files. However, using `.aab` with fast deployment
+> will be slower than using `.apk` because the `.aab` file must be processed through `bundletool`
+> for packaging and installation.
 
 To test your asset packs add the following to the first `<PropertyGroup/>` in your `.csproj`.