Initial commit: ClawdDotNet

Import des bestehenden Projektstands in Git.
- .NET 10 WinForms Anwendung (Multi-Agent / Tool-System)
- .gitignore fuer Build-Artefakte, Secrets und Runtime-Daten ergaenzt

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Services/JobHistoryService.cs

@@ -0,0 +1,95 @@
+using System.Text.Json;
+using ClawdDotNet.Models;
+
+namespace ClawdDotNet.Services;
+
+/// <summary>
+/// Thread-safe JSON persistence for job execution history.
+/// Uses file locking to handle concurrent access from multiple schedulers.
+/// </summary>
+public sealed class JobHistoryService
+{
+    private readonly string _filePath;
+    private readonly Lock _lock = new();
+    private readonly int _maxEntries;
+    private List<JobHistoryEntry> _entries = new();
+
+    private static readonly JsonSerializerOptions JsonOptions = new()
+    {
+        WriteIndented = true
+    };
+
+    public JobHistoryService(string instancePath, int maxEntries = 500)
+    {
+        _filePath = Path.Combine(instancePath, "job_history.json");
+        _maxEntries = maxEntries;
+        Load();
+    }
+
+    /// <summary>
+    /// Adds a new entry to the history (thread-safe, persists immediately).
+    /// </summary>
+    public void Add(JobHistoryEntry entry)
+    {
+        lock (_lock)
+        {
+            _entries.Insert(0, entry); // newest first
+
+            // Trim old entries
+            if (_entries.Count > _maxEntries)
+                _entries = _entries.Take(_maxEntries).ToList();
+
+            Save();
+        }
+    }
+
+    /// <summary>
+    /// Returns a snapshot of all entries (newest first).
+    /// </summary>
+    public List<JobHistoryEntry> GetAll()
+    {
+        lock (_lock)
+            return new List<JobHistoryEntry>(_entries);
+    }
+
+    private void Load()
+    {
+        lock (_lock)
+        {
+            try
+            {
+                if (!File.Exists(_filePath))
+                {
+                    _entries = new List<JobHistoryEntry>();
+                    return;
+                }
+
+                using var stream = new FileStream(_filePath, FileMode.Open, FileAccess.Read, FileShare.Read);
+                _entries = JsonSerializer.Deserialize<List<JobHistoryEntry>>(stream, JsonOptions)
+                    ?? new List<JobHistoryEntry>();
+            }
+            catch
+            {
+                _entries = new List<JobHistoryEntry>();
+            }
+        }
+    }
+
+    private void Save()
+    {
+        try
+        {
+            var tmpPath = _filePath + ".tmp";
+            using (var stream = new FileStream(tmpPath, FileMode.Create, FileAccess.Write, FileShare.None))
+            {
+                JsonSerializer.Serialize(stream, _entries, JsonOptions);
+            }
+
+            File.Move(tmpPath, _filePath, overwrite: true);
+        }
+        catch
+        {
+            // Silently ignore write failures — next save will retry
+        }
+    }
+}