feat(worker): add WorktreeMaintenanceService for idle-worktree cleanup

src/ClaudeDo.Data/Git/GitService.cs

@@ -73,6 +73,21 @@ public sealed class GitService
         return stdout;
     }
 
+    /// <summary>
+    /// Full diff between <paramref name="baseRef"/> and the current working tree
+    /// (committed-on-branch changes + uncommitted work). Used for viewing a Claude
+    /// task's total impact relative to where the branch started.
+    /// </summary>
+    public async Task<string> GetBranchDiffAsync(string worktreePath, string baseRef, CancellationToken ct = default)
+    {
+        var (exitCode, stdout, _) = await RunGitAsync(worktreePath,
+            ["diff", baseRef], ct);
+        if (exitCode == 0 && !string.IsNullOrWhiteSpace(stdout))
+            return stdout;
+        // Fallback: whatever the worktree has vs HEAD (uncommitted only).
+        return await GetDiffAsync(worktreePath, ct);
+    }
+
     public async Task<string> DiffStatAsync(string worktreePath, string baseCommit, string headCommit, CancellationToken ct = default)
     {
         var (exitCode, stdout, stderr) = await RunGitAsync(worktreePath,
@@ -93,6 +108,41 @@ public sealed class GitService
             throw new InvalidOperationException($"git worktree remove failed (exit {exitCode}): {stderr}");
     }
 
+    public async Task<List<string>> ListWorktreePathsForBranchAsync(string repoDir, string branchName, CancellationToken ct = default)
+    {
+        var (exitCode, stdout, _) = await RunGitAsync(repoDir, ["worktree", "list", "--porcelain"], ct);
+        if (exitCode != 0) return new();
+
+        var target = $"refs/heads/{branchName}";
+        var paths = new List<string>();
+        string? currentPath = null;
+        foreach (var raw in stdout.Split('\n'))
+        {
+            var line = raw.TrimEnd('\r');
+            if (line.StartsWith("worktree ", StringComparison.Ordinal))
+            {
+                currentPath = line["worktree ".Length..].Trim();
+            }
+            else if (line.StartsWith("branch ", StringComparison.Ordinal))
+            {
+                var b = line["branch ".Length..].Trim();
+                if (b == target && currentPath is not null) paths.Add(currentPath);
+            }
+            else if (string.IsNullOrWhiteSpace(line))
+            {
+                currentPath = null;
+            }
+        }
+        return paths;
+    }
+
+    public async Task WorktreePruneAsync(string repoDir, CancellationToken ct = default)
+    {
+        var (exitCode, _, stderr) = await RunGitAsync(repoDir, ["worktree", "prune"], ct);
+        if (exitCode != 0)
+            throw new InvalidOperationException($"git worktree prune failed (exit {exitCode}): {stderr}");
+    }
+
     public async Task BranchDeleteAsync(string repoDir, string branchName, bool force = false, CancellationToken ct = default)
     {
         var flag = force ? "-D" : "-d";

src/ClaudeDo.Data/Repositories/WorktreeRepository.cs

@@ -40,4 +40,17 @@ public sealed class WorktreeRepository
     {
         await _context.Worktrees.Where(w => w.TaskId == taskId).ExecuteDeleteAsync(ct);
     }
+
+    public async Task<List<WorktreeEntity>> GetAllAsync(CancellationToken ct = default)
+    {
+        return await _context.Worktrees.AsNoTracking().ToListAsync(ct);
+    }
+
+    public async Task<List<WorktreeEntity>> GetByStatesAsync(
+        IReadOnlyCollection<WorktreeState> states, CancellationToken ct = default)
+    {
+        return await _context.Worktrees.AsNoTracking()
+            .Where(w => states.Contains(w.State))
+            .ToListAsync(ct);
+    }
 }