Update Azure.ResourceManager.Resources API version to latest

[anthony-c-martin]

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[Copilot]

Pull Request Overview

This PR updates the Azure.ResourceManager.Resources API version references in the autorest.md file and introduces several new overloads and property type changes across the ARM resource model APIs.

• Updated API version URLs in autorest.md from 2024-11-01 to 2025-04-01 and added new input file references.
• Introduced a new Identity property on ArmDeploymentContent and updated collection types (e.g. changing OutputResources and ValidatedResources from SubResource lists to ResourceReference lists) along with additional overloads for methods such as ArmDeploymentProperties and WhatIfChange.

Reviewed Changes

Copilot reviewed 46 out of 46 changed files in this pull request and generated no comments.

File	Description
sdk/resources/Azure.ResourceManager.Resources/src/autorest.md	Updated API version strings and input file URLs to reflect the latest API version.
sdk/resources/Azure.ResourceManager.Resources/api/Azure.ResourceManager.Resources.netstandard2.0.cs	Added new properties, overloads, and updated collection types as part of the API update.
sdk/resources/Azure.ResourceManager.Resources/api/Azure.ResourceManager.Resources.net8.0.cs	Mirrored changes from netstandard2.0 with similar new overloads and property updates.

Comments suppressed due to low confidence (3)

sdk/resources/Azure.ResourceManager.Resources/api/Azure.ResourceManager.Resources.netstandard2.0.cs:1358

• [nitpick] Multiple overloads of ArmDeploymentProperties are introduced with subtle differences; consider adding detailed XML documentation comments to clarify their intended usage and parameter differences.

public static Azure.ResourceManager.Resources.Models.ArmDeploymentProperties ArmDeploymentProperties(System.BinaryData template, Azure.ResourceManager.Resources.Models.ArmDeploymentTemplateLink templateLink, System.BinaryData parameters, ...)

sdk/resources/Azure.ResourceManager.Resources/api/Azure.ResourceManager.Resources.netstandard2.0.cs:1409

• [nitpick] The addition of an extension parameter in the WhatIfChange overloads enhances functionality; please ensure that XML documentation is updated to clarify the scenarios where each overload should be used.

public static Azure.ResourceManager.Resources.Models.WhatIfChange WhatIfChange(string resourceId = null, string deploymentId = null, string symbolicName = null, System.BinaryData identifiers = null, Azure.ResourceManager.Resources.Models.DeploymentExtensionDefinition extension = null, ...)

sdk/resources/Azure.ResourceManager.Resources/api/Azure.ResourceManager.Resources.netstandard2.0.cs:1226

• The change from IReadOnlyList to IReadOnlyList for OutputResources appears intentional; please ensure that corresponding client code and serialization logic are updated consistently.

public System.Collections.Generic.IReadOnlyList<Azure.ResourceManager.Resources.Models.ResourceReference> OutputResources { get { throw null; } }