Added a SWOT analysis assistant (#1122)

Co-authored-by: hart_s3 <sabrina.hartmann@dlr.de>

app/Tests/Assistants/SWOTAnalysis/SwotContextualKnowledgeTests.cs

@@ -0,0 +1,45 @@
+using AIStudio.Assistants.SWOTAnalysis;
+using AIStudio.Chat;
+
+namespace AIStudio.Tests.Assistants.SWOTAnalysis;
+
+[TestFixture]
+public sealed class SwotContextualKnowledgeTests
+{
+    private const string DOCUMENTS = "The following files are attached to this message: annual-report.pdf";
+
+    [Test]
+    public void WithoutMaterialTheSectionSaysSo() =>
+        Assert.That(SwotContextualKnowledge.NONE.Describe(), Is.EqualTo("No additional contextual knowledge was provided."));
+
+    [Test]
+    public void DocumentsAloneAreTheSection() =>
+        Assert.That(new SwotContextualKnowledge(DOCUMENTS, []).Describe(), Is.EqualTo(DOCUMENTS));
+
+    [Test]
+    public void ImagesAloneAreNamedByTheirCount()
+    {
+        var oneImage = new SwotContextualKnowledge(string.Empty, [Image("chart.png")]);
+        var twoImages = new SwotContextualKnowledge(string.Empty, [Image("chart.png"), Image("photo.jpg")]);
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(oneImage.Describe(), Is.EqualTo("The image attached to this message belongs to the contextual knowledge."));
+            Assert.That(twoImages.Describe(), Is.EqualTo("The 2 images attached to this message belong to the contextual knowledge."));
+        });
+    }
+
+    [Test]
+    public void ImagesFollowTheDocuments()
+    {
+        var description = new SwotContextualKnowledge(DOCUMENTS, [Image("chart.png")]).Describe();
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(description, Does.StartWith(DOCUMENTS));
+            Assert.That(description, Does.EndWith("The image attached to this message belongs to the contextual knowledge."));
+        });
+    }
+
+    private static FileAttachmentImage Image(string fileName) => new(fileName, $"/tmp/{fileName}", 1024);
+}