WaitFor PR feedback (#5500)

Follow up feedback for #5394.

Author: eerhardt

src/Aspire.Hosting/ApplicationModel/CustomResourceSnapshot.cs

@@ -158,5 +158,5 @@ public static class KnownResourceStates
     /// <summary>
     /// List of terminal states.
     /// </summary>
-    public static readonly string[] TerminalStates = [Finished, FailedToStart, Exited];
+    public static readonly IReadOnlyList<string> TerminalStates = [Finished, FailedToStart, Exited];
 }

src/Aspire.Hosting/ApplicationModel/ResourceNotificationService.cs

@@ -104,20 +104,19 @@ public async Task<string> WaitForResourceAsync(string resourceName, IEnumerable<
     }
 
     /// <summary>
-    /// Waits for a resource to reach one of the specified states. See <see cref="KnownResourceStates"/> for common states.
+    /// Waits until a resource satisfies the specified predicate.
     /// </summary>
     /// <remarks>
-    /// This method returns a task that will complete when the resource reaches one of the specified target states. If the resource
-    /// is already in the target state, the method will return immediately.<br/>
-    /// If the resource doesn't reach one of the target states before <paramref name="cancellationToken"/> is signaled, this method
+    /// This method returns a task that will complete when the specified predicate returns <see langword="true" />.<br/>
+    /// If the predicate isn't satisfied before <paramref name="cancellationToken"/> is signaled, this method
     /// will throw <see cref="OperationCanceledException"/>.
     /// </remarks>
     /// <param name="resourceName">The name of the resource.</param>
     /// <param name="predicate">A predicate which is evaluated for each <see cref="ResourceEvent"/> for the selected resource.</param>
     /// <param name="cancellationToken">A cancellation token that cancels the wait operation when signaled.</param>
     /// <returns>A <see cref="Task{ResourceEvent}"/> representing the wait operation and which of the target states the resource reached.</returns>
     [System.Diagnostics.CodeAnalysis.SuppressMessage("ApiDesign", "RS0026:Do not add multiple public overloads with optional parameters",
-                                                     Justification = "targetState(s) parameters are mutually exclusive.")]
+                                                     Justification = "predicate and targetState(s) parameters are mutually exclusive.")]
     public async Task<ResourceEvent> WaitForResourceAsync(string resourceName, Func<ResourceEvent, bool> predicate, CancellationToken cancellationToken = default)
     {
         using var watchCts = CancellationTokenSource.CreateLinkedTokenSource(_applicationStopping, cancellationToken);

src/Aspire.Hosting/PublicAPI.Unshipped.txt

@@ -83,5 +83,5 @@ static Aspire.Hosting.ContainerResourceBuilderExtensions.WithBuildArg<T>(this As
 static Aspire.Hosting.ContainerResourceBuilderExtensions.WithBuildSecret<T>(this Aspire.Hosting.ApplicationModel.IResourceBuilder<T!>! builder, string! name, Aspire.Hosting.ApplicationModel.IResourceBuilder<Aspire.Hosting.ApplicationModel.ParameterResource!>! value) -> Aspire.Hosting.ApplicationModel.IResourceBuilder<T!>!
 static Aspire.Hosting.ProjectResourceBuilderExtensions.AddProject(this Aspire.Hosting.IDistributedApplicationBuilder! builder, string! name, string! projectPath, System.Action<Aspire.Hosting.ProjectResourceOptions!>! configure) -> Aspire.Hosting.ApplicationModel.IResourceBuilder<Aspire.Hosting.ApplicationModel.ProjectResource!>!
 static Aspire.Hosting.ProjectResourceBuilderExtensions.AddProject<TProject>(this Aspire.Hosting.IDistributedApplicationBuilder! builder, string! name, System.Action<Aspire.Hosting.ProjectResourceOptions!>! configure) -> Aspire.Hosting.ApplicationModel.IResourceBuilder<Aspire.Hosting.ApplicationModel.ProjectResource!>!
-static readonly Aspire.Hosting.ApplicationModel.KnownResourceStates.TerminalStates -> string![]!
+static readonly Aspire.Hosting.ApplicationModel.KnownResourceStates.TerminalStates -> System.Collections.Generic.IReadOnlyList<string!>!
 static readonly Aspire.Hosting.ApplicationModel.KnownResourceStates.Waiting -> string!