Fix frontmatter parsing for quote workflow

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

src/Yavsc.Server/Models/Billing/FrontmatterOffreResult.cs

@@ -2,7 +2,7 @@ namespace Yavsc.Server.Models.Billing;
 
 public class FrontmatterOffreResult
 {
-    public string Formulaire { get; set; }
-    public string Devis { get; set; }
-    public string Corps { get; set; }  // le Markdown sans l'en-tête
+    public string Formulaire { get; set; } = string.Empty;
+    public string Devis { get; set; } = string.Empty;
+    public string Corps { get; set; } = string.Empty;  // le Markdown sans l'en-tête
 }

src/Yavsc.Server/Services/FrontmatterParser.cs

@@ -6,8 +6,8 @@ namespace Yavsc.Server.Services;
 
 public static class FrontmatterParser
 {
-    public  const string YamlHeader = "---\n";
-    public  const string YamlSeparator = "\n---";
+    public const string YamlHeader = "---";
+    public const string YamlSeparator = "---";
 
     private static readonly IDeserializer _deserializer =
         new DeserializerBuilder()
@@ -17,17 +17,23 @@ public static class FrontmatterParser
 
     public static FrontmatterOffreResult Parse(string markdown)
     {
-        // Le contenu doit commencer par ----
-        if (!markdown.TrimStart().StartsWith(YamlHeader, StringComparison.Ordinal))
+        ArgumentNullException.ThrowIfNull(markdown);
+
+        var trimmed = markdown.TrimStart();
+
+        if (!trimmed.StartsWith(YamlHeader, StringComparison.Ordinal))
             return new FrontmatterOffreResult { Corps = markdown };
 
-        var parts = markdown.Substring(YamlHeader.Length).Trim().Split(new[] { YamlSeparator }, 2,
-                           StringSplitOptions.None);
+        var afterOpeningMarker = trimmed[YamlHeader.Length..];
+        var parts = afterOpeningMarker
+            .Split(new[] { "\r\n---", "\n---" }, 2, StringSplitOptions.None);
+
         if (parts.Length < 2)
             return new FrontmatterOffreResult { Corps = markdown };
-        var yamlBlock = parts[0];
-        var corps     = parts[1];
-        var meta = _deserializer.Deserialize<FrontmatterOffreResult>(yamlBlock);
+
+        var yamlBlock = parts[0].Trim();
+        var corps = parts[1].TrimStart();
+        var meta = _deserializer.Deserialize<FrontmatterOffreResult>(yamlBlock) ?? new FrontmatterOffreResult();
         meta.Corps = corps;
         return meta;
     }

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);
+    }
+}