Initial commit: EngineeringSync v1.0.0

Vollständige Implementierung des EngineeringSync-Middleware-Tools:
- Windows Service (Kestrel :5050) mit FileSystemWatcher + SignalR
- WPF Tray-App mit PendingChanges- und Projektverwaltungs-Fenster
- Setup-Wizard (8-Schritte-Installer)
- SQLite/EF Core Datenschicht (WAL-Modus)
- SHA-256-basiertes Debouncing (2s Fenster)
- Backup-System mit konfigurierbarer Aufbewahrung

Bugfixes & Verbesserungen:
- BUG-1: AppDbContext OnConfiguring invertierte Bedingung behoben
- BUG-2: Event-Handler-Leak in TrayApp (Fenster-Singleton-Pattern)
- BUG-3: ProjectConfigChanged SignalR-Signal in allen CRUD-Endpoints
- BUG-5: Rename-Sync löscht alte Datei im Simulations-Ordner
- BUG-6: Doppeltes Dispose von SignalR verhindert
- BUG-7: Registry-Deinstallation nur EngineeringSync-Eintrag entfernt
- S1: Path-Traversal-Schutz via SafeCombine() im SyncManager
- E1: FSW Buffer 64KB + automatischer Re-Scan bei Overflow
- E2: Retry-Logik (3x) für gesperrte Dateien mit exponentiellem Backoff
- E4: Channel.Writer.TryComplete() beim Shutdown
- C2: HubMethodNames-Konstanten statt Magic Strings
- E3: Pagination in Changes-API (page/pageSize Query-Parameter)
- A1: Fire-and-Forget mit try/catch + Logging

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

EngineeringSync.TrayApp/Services/ApiClient.cs

@@ -0,0 +1,59 @@
+using System.Net.Http;
+using System.Net.Http.Json;
+using EngineeringSync.Domain.Entities;
+
+namespace EngineeringSync.TrayApp.Services;
+
+public class ApiClient(HttpClient http)
+{
+    private const string Base = "http://localhost:5050/api";
+
+    public Task<List<ProjectConfig>?> GetProjectsAsync() =>
+        http.GetFromJsonAsync<List<ProjectConfig>>($"{Base}/projects");
+
+    public Task<List<PendingChange>?> GetChangesAsync(Guid projectId) =>
+        http.GetFromJsonAsync<List<PendingChange>>($"{Base}/changes/{projectId}");
+
+    public Task<List<ScanResultDto>?> ScanFoldersAsync(string engineeringPath, string simulationPath, string fileExtensions) =>
+        http.GetFromJsonAsync<List<ScanResultDto>>($"{Base}/projects/scan?engineeringPath={Uri.EscapeDataString(engineeringPath)}&simulationPath={Uri.EscapeDataString(simulationPath)}&fileExtensions={Uri.EscapeDataString(fileExtensions)}");
+
+    public async Task CreateProjectAsync(CreateProjectDto dto)
+    {
+        var resp = await http.PostAsJsonAsync($"{Base}/projects", dto);
+        resp.EnsureSuccessStatusCode();
+    }
+
+    public async Task UpdateProjectAsync(Guid id, UpdateProjectDto dto)
+    {
+        var resp = await http.PutAsJsonAsync($"{Base}/projects/{id}", dto);
+        resp.EnsureSuccessStatusCode();
+    }
+
+    public async Task DeleteProjectAsync(Guid id)
+    {
+        var resp = await http.DeleteAsync($"{Base}/projects/{id}");
+        resp.EnsureSuccessStatusCode();
+    }
+
+    public async Task SyncChangesAsync(List<Guid> ids)
+    {
+        var resp = await http.PostAsJsonAsync($"{Base}/sync", new { ChangeIds = ids });
+        resp.EnsureSuccessStatusCode();
+    }
+
+    public async Task IgnoreChangesAsync(List<Guid> ids)
+    {
+        var resp = await http.PostAsJsonAsync($"{Base}/ignore", new { ChangeIds = ids });
+        resp.EnsureSuccessStatusCode();
+    }
+}
+
+public record CreateProjectDto(string Name, string EngineeringPath, string SimulationPath,
+    string FileExtensions, bool IsActive = true, bool BackupEnabled = true,
+    string? BackupPath = null, int MaxBackupsPerFile = 0);
+
+public record UpdateProjectDto(string Name, string EngineeringPath, string SimulationPath,
+    string FileExtensions, bool IsActive, bool BackupEnabled = true,
+    string? BackupPath = null, int MaxBackupsPerFile = 0);
+
+public record ScanResultDto(string RelativePath, string ChangeType, long Size, DateTime LastModified);