feat(dapr): add IValueProvider support for component metadata configuration

[gabynevada]

Summary

• Adds support for using IValueProvider (including EndpointReference) in Dapr component metadata configuration
• Enables dynamic endpoint resolution for Dapr components at runtime
• Maintains backward compatibility with existing string and ParameterResource overloads

Changes

• Added new WithMetadata overload accepting IValueProvider for flexible metadata configuration
• Implemented deferred value resolution through environment variables and secretKeyRef mechanism
• Added DaprComponentValueProviderAnnotation to track value providers requiring resolution
• Updated lifecycle hook to resolve and inject endpoint values at runtime
• Enhanced DaprComponentSchema with async value resolution capabilities

Test Plan

• Added unit tests for EndpointReference metadata configuration
• Added tests for value provider resolution in component schema
• Added tests for multiple endpoint references
• Updated example to demonstrate Redis endpoint usage with the new feature
• Verified backward compatibility with existing metadata configuration methods

Example Usage

var redis = builder.AddRedis("redis");

var redisHost= redis.Resource.PrimaryEndpoint.Property(EndpointProperty.Host);
var redisTargetPort = redis.Resource.PrimaryEndpoint.Property(EndpointProperty.TargetPort);

var pubsub = builder
  .AddDaprPubSub("pubsub")
  .WithMetadata(
    "redisHost",
    ReferenceExpression.Create(
      $"{redisHost}:{redisTargetPort}"
    )
  );

This allows Dapr components to dynamically reference Aspire resource endpoints that are only known at runtime.

Closes #604

[davidfowl]

Did you implement the waiting? To make this work, the resource needs a lifecycle, see https://github.com/dotnet/aspire/blob/main/docs/specs/appmodel.md#built-in-resources--lifecycle.

When you implement IResourceWithWaitSupport, at some point you have to raise https://github.com/dotnet/aspire/blob/364382724b4cd3590ec75010525ce36ef0b5e769/src/Aspire.Hosting/ConnectionStringBuilderExtensions.cs#L92

[gabynevada]

Implemented it, don't know if it's the correct approach but I followed the examples. Also implemented on the IDaprComponentResource as it seems it was missing support

[FullStackChef]

@gabynevada just checking the state of the PR - are you wanting this re-reviewed? is it ready to merge?

[gabynevada]

@FullStackChef was occupied on work so could not do the final changes. Pushed the final changes so that the dapr component resources have a lifecycle and thus other resources can wait for them to get to the running state.

Let me know if anything needs to be changed!