Add C# bridges and coordinator service

- geviscope-bridge: GeViScope SDK REST wrapper (:7720)
- gcore-bridge: G-Core SDK REST wrapper (:7721)
- geviserver-bridge: GeViServer REST wrapper (:7710)
- copilot-coordinator: WebSocket coordination hub (:8090)

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

.gitignore

@@ -38,5 +38,9 @@ test_coordinator.ps1
 package.json
 nul
 
+# .NET build outputs
+**/bin/
+**/obj/
+
 # Decompiled text dumps
 C*DEVCOPILOT_D6*