feat(git): add ListLocalBranchesAsync

src/ClaudeDo.Data/Git/GitService.cs

@@ -160,6 +160,19 @@ public sealed class GitService
         return stdout.Trim();
     }
 
+    public async Task<List<string>> ListLocalBranchesAsync(string repoDir, CancellationToken ct = default)
+    {
+        var (exitCode, stdout, stderr) = await RunGitAsync(repoDir,
+            ["branch", "--format=%(refname:short)"], ct);
+        if (exitCode != 0)
+            throw new InvalidOperationException($"git branch --format failed (exit {exitCode}): {stderr}");
+
+        return stdout
+            .Split('\n', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)
+            .Where(s => s.Length > 0)
+            .ToList();
+    }
+
     public async Task MergeFfOnlyAsync(string repoDir, string branchName, CancellationToken ct = default)
     {
         var (exitCode, _, stderr) = await RunGitAsync(repoDir, ["merge", "--ff-only", branchName], ct);

tests/ClaudeDo.Worker.Tests/Runner/GitServiceMergeTests.cs

@@ -34,4 +34,19 @@ public class GitServiceMergeTests : IDisposable
         Assert.True(branch == "main" || branch == "master",
             $"Expected main or master, got '{branch}'");
     }
+
+    [Fact]
+    public async Task ListLocalBranchesAsync_AfterCreatingSecondBranch_ReturnsBoth()
+    {
+        if (!GitRepoFixture.IsGitAvailable()) return;
+
+        var repo = NewRepo();
+        GitRepoFixture.RunGit(repo.RepoDir, "branch", "feature/x");
+
+        var git = new GitService();
+        var branches = await git.ListLocalBranchesAsync(repo.RepoDir);
+
+        Assert.Contains("feature/x", branches);
+        Assert.True(branches.Any(b => b == "main" || b == "master"));
+    }
 }