refactor: rename sidecar host to Aryx

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

sidecar/tests/Aryx.AgentHost.Tests/StreamingTextMergerTests.cs

@@ -0,0 +1,58 @@
+using Aryx.AgentHost.Services;
+
+namespace Aryx.AgentHost.Tests;
+
+public sealed class StreamingTextMergerTests
+{
+    [Fact]
+    public void Merge_AppendsPlainDeltas()
+    {
+        Assert.Equal("I am going", StreamingTextMerger.Merge("I am", " going"));
+    }
+
+    [Fact]
+    public void Merge_ReplacesWithGrowingSnapshot()
+    {
+        Assert.Equal("I am going", StreamingTextMerger.Merge("I am", "I am going"));
+    }
+
+    [Fact]
+    public void Merge_PreservesCurrentTextForDuplicateSubset()
+    {
+        Assert.Equal("I am going", StreamingTextMerger.Merge("I am going", "going"));
+    }
+
+    [Fact]
+    public void Merge_UsesOverlapToAvoidDuplicateJoins()
+    {
+        Assert.Equal("Hello world", StreamingTextMerger.Merge("Hello wor", "world"));
+    }
+
+    [Fact]
+    public void Merge_ReplacesWithRevisedSnapshotWhenMostTokensOverlap()
+    {
+        const string current = "I mirror the existing button pattern and add brief toggle docs.";
+        const string incoming = "I found the standalone component pattern and I am updating toggle docs next.";
+
+        Assert.Equal(incoming, StreamingTextMerger.Merge(current, incoming));
+    }
+
+    [Fact]
+    public void Merge_InsertsWhitespaceWhenSnapshotLikeUpdatesWouldOtherwiseGlueWordsTogether()
+    {
+        Assert.Equal(
+            "How about The **Ashen Crown** feels",
+            StreamingTextMerger.Merge("How about", "The **Ashen Crown** feels"));
+        Assert.Equal(
+            "The **Ashen Crown** feels classic and timeless.",
+            StreamingTextMerger.Merge("The **Ashen Crown** feels", "classic and timeless."));
+    }
+
+    [Fact]
+    public void Merge_InsertsNewlineBeforeStreamedMarkdownBlockMarkers()
+    {
+        Assert.Equal(
+            "If you want, I can also give you\n- darker titles",
+            StreamingTextMerger.Merge("If you want, I can also give you", "- darker titles"));
+    }
+}