Fix frontmatter parsing for quote workflow

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

src/test/Yavsc.Server.Tests/FrontmatterParserTests.cs

@@ -0,0 +1,42 @@
+using Yavsc.Server.Services;
+
+namespace Yavsc.Server.Tests;
+
+public class FrontmatterParserTests
+{
+    [Fact]
+    public void Parse_extracts_formulaire_devis_and_body_for_unix_line_endings()
+    {
+        const string markdown = "---\nformulaire: Prestation Musicale\ndevis: Arrangement Orchestral\n---\n\nContenu du devis\n";
+
+        var result = FrontmatterParser.Parse(markdown);
+
+        Assert.Equal("Prestation Musicale", result.Formulaire);
+        Assert.Equal("Arrangement Orchestral", result.Devis);
+        Assert.Equal("Contenu du devis", result.Corps.Trim());
+    }
+
+    [Fact]
+    public void Parse_accepts_windows_line_endings()
+    {
+        const string markdown = "---\r\nformulaire: Prestation Musicale\r\ndevis: Arrangement Orchestral\r\n---\r\n\r\nContenu du devis\r\n";
+
+        var result = FrontmatterParser.Parse(markdown);
+
+        Assert.Equal("Prestation Musicale", result.Formulaire);
+        Assert.Equal("Arrangement Orchestral", result.Devis);
+        Assert.Equal("Contenu du devis", result.Corps.Trim());
+    }
+
+    [Fact]
+    public void Parse_returns_original_markdown_when_no_frontmatter_is_present()
+    {
+        const string markdown = "# Hello\n\nThis is plain markdown.";
+
+        var result = FrontmatterParser.Parse(markdown);
+
+        Assert.Equal(string.Empty, result.Formulaire);
+        Assert.Equal(string.Empty, result.Devis);
+        Assert.Equal(markdown, result.Corps);
+    }
+}