Normalize scalar frontmatter lists

MeetingAssistant.Tests/MeetingNoteStoreTests.cs

@@ -105,6 +105,36 @@ public sealed class MeetingNoteStoreTests
         Assert.Equal(userNotes, reloaded.UserNotes);
     }
 
+    [Fact]
+    public async Task ReadConvertsScalarListFrontmatterToSingleItemLists()
+    {
+        var (vaultRoot, store) = CreateStore();
+        var notePath = Path.Combine(vaultRoot, "Meetings", "Notes", "manual.md");
+        Directory.CreateDirectory(Path.GetDirectoryName(notePath)!);
+        await File.WriteAllTextAsync(
+            notePath,
+            """
+            ---
+            title: Manual frontmatter
+            start_time: "2026-05-19T10:00:00.0000000+02:00"
+            end_time: ""
+            attendees: Ada
+            projects: Meeting Assistant
+            transcript: "[[../Transcripts/manual-transcript|Transcript]]"
+            assistant_context: "[[../Assistant Context/manual-context|Assistant Context]]"
+            summary: "[[../Summaries/manual-summary|Summary]]"
+            ---
+
+            User notes.
+            """);
+
+        var loaded = await store.ReadAsync(notePath, CancellationToken.None);
+
+        Assert.Equal(["Ada"], loaded.Frontmatter.Attendees);
+        Assert.Equal(["Meeting Assistant"], loaded.Frontmatter.Projects);
+        Assert.Equal("User notes.", loaded.UserNotes);
+    }
+
     [Fact]
     public void ActionLinkEscapesSummaryFileName()
     {

MeetingAssistant.Tests/ProjectKnowledgeToolTests.cs

@@ -63,6 +63,34 @@ public sealed class ProjectKnowledgeToolTests
             await tools.Search("alpha"));
     }
 
+    [Fact]
+    public async Task ListProjectsAcceptsScalarProjectFrontmatter()
+    {
+        var root = Path.Combine(Path.GetTempPath(), "meeting-assistant-tests", Guid.NewGuid().ToString("N"));
+        var projectsRoot = Path.Combine(root, "Projects");
+        Directory.CreateDirectory(Path.Combine(projectsRoot, "MeetingAssistant"));
+        var artifacts = CreateArtifacts(root);
+        Directory.CreateDirectory(Path.GetDirectoryName(artifacts.MeetingNotePath)!);
+        await File.WriteAllTextAsync(
+            artifacts.MeetingNotePath,
+            """
+            ---
+            projects: MeetingAssistant
+            ---
+            """);
+        var tools = new MeetingSummaryTools(
+            artifacts,
+            new MeetingAssistantOptions
+            {
+                Vault =
+                {
+                    ProjectsFolder = projectsRoot
+                }
+            });
+
+        Assert.Equal("MeetingAssistant", await tools.ListProjects());
+    }
+
     [Fact]
     public async Task WriteProjectFileSupportsAppendReplaceInsertOverwriteAndCreate()
     {