Added file patterns and exclusions to folder data sources (#1057)

Co-authored-by: Thorsten Sommer <SommerEngineering@users.noreply.github.com>

app/Tests/Tools/FileEnumerationResultTests.cs

@@ -0,0 +1,32 @@
+using AIStudio.Tools.Services;
+
+namespace AIStudio.Tests.Tools;
+
+public sealed class FileEnumerationResultTests
+{
+    [Test]
+    public void PatternExclusionsAreSummarizedByFileTypeWithoutKeepingEveryPath()
+    {
+        var directoryPath = Path.Combine(Path.GetTempPath(), "test-data");
+        var result = new FileEnumerationResult();
+
+        result.AddFilePatternExclusion(Path.Combine(directoryPath, "one.PDF"));
+        result.AddFilePatternExclusion(Path.Combine(directoryPath, "two.pdf"));
+        result.AddFilePatternExclusion(Path.Combine(directoryPath, "README"));
+        result.AddFilePatternExclusion(Path.Combine(directoryPath, "Dockerfile"));
+        result.AddFilePatternExclusion(Path.Combine(directoryPath, "nested", "dockerfile"));
+        result.AddFilePatternExclusion(Path.Combine(directoryPath, "Caddyfile"));
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(result.FilePatternExclusionCount, Is.EqualTo(6));
+            Assert.That(result.FilePatternExclusions, Is.EquivalentTo(new[]
+            {
+                new DataSourceEmbeddingFilePatternGroup(string.Empty, 1),
+                new DataSourceEmbeddingFilePatternGroup("Caddyfile", 1),
+                new DataSourceEmbeddingFilePatternGroup("Dockerfile", 2),
+                new DataSourceEmbeddingFilePatternGroup(".pdf", 2),
+            }));
+        });
+    }
+}