test: add unit tests and sample notes

internal/rag/chunker_test.go

@@ -0,0 +1,41 @@
+package rag
+
+import "testing"
+
+func TestChunkMarkdown_ByHeaders(t *testing.T) {
+	md := `# Title
+
+## Section 1
+
+Content of section 1.
+
+## Section 2
+
+Content of section 2.`
+
+	chunks := ChunkMarkdown(md, 1000)
+	if len(chunks) < 2 {
+		t.Errorf("expected at least 2 chunks, got %d", len(chunks))
+	}
+}
+
+func TestChunkMarkdown_SmallContent(t *testing.T) {
+	md := "Just a short note with no headers."
+	chunks := ChunkMarkdown(md, 500)
+	if len(chunks) != 1 {
+		t.Errorf("expected 1 chunk, got %d", len(chunks))
+	}
+}
+
+func TestChunkMarkdown_SplitLargeSection(t *testing.T) {
+	md := `## Big Section
+
+Paragraph one with enough content to make this section reasonably long for testing purposes.
+
+Paragraph two with more content that should be in a separate chunk when the max size is small.`
+
+	chunks := ChunkMarkdown(md, 80)
+	if len(chunks) < 2 {
+		t.Errorf("expected at least 2 chunks for large section, got %d", len(chunks))
+	}
+}