TASK 4 ship step 5.5: social bar bug fixes + bar on the live output — direction-snap drag (SocialBarSnap.Decide + ClearValue, local Canvas.Top was overriding the binding), fediverse nodeinfo subdomain probing + load-time heal (settable FediverseSoftware), SocialBarRenderer strip blitted above the flash via a re-read FramePump socialBar seam — 155 tests passing, 0 warnings

ytLive.Tests/SocialsDialogViewModelTests.cs

@@ -15,6 +15,9 @@ public class SocialsDialogViewModelTests
     {
         public int LookupCount { get; private set; }
 
+        public Task<string?> ResolveFediverseSoftwareAsync(string domain, CancellationToken ct)
+            => Task.FromResult<string?>("mastodon");
+
         public Task<SocialLookupResult> LookupAsync(SocialService service, string handleOrUrl, CancellationToken ct)
         {
             LookupCount++;
@@ -51,6 +54,9 @@ public class SocialsDialogViewModelTests
 
         public Task<SocialLookupResult> LookupAsync(SocialService service, string handleOrUrl, CancellationToken ct)
             => Gate.Task;
+
+        public Task<string?> ResolveFediverseSoftwareAsync(string domain, CancellationToken ct)
+            => Task.FromResult<string?>(null);
     }
 
     private sealed class SignInFake