Initial commit: HC900 Crawler

Honeywell HC900을 Modbus TCP로 직접 폴링 → gRPC → C# 크롤러 → PostgreSQL.
기존 Experion OPC UA 데이터 경로를 HC900 직접 통신으로 대체.

- industrial-comm/cpp: C++ Modbus 게이트웨이 (gRPC 서버)
- src: C# .NET 8 ASP.NET Core 크롤러 + 웹 UI (3-Layer)
- mcp-server: Python FastMCP (RAG/NL2SQL/P&ID)
- 다중 컨트롤러(N-Controller) 지원

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

config/gateway-config.json

@@ -0,0 +1,19 @@
+{
+  "shared": {
+    "binaryPath": "/home/windpacer/projects/hc900_ax/industrial-comm/cpp/build/hc900_gateway",
+    "ldLibraryPath": "/tmp/grpc_local/usr/lib/aarch64-linux-gnu:/tmp/absl_local/usr/lib/aarch64-linux-gnu",
+    "logDir": "/tmp"
+  },
+  "controllers": [
+    {
+      "id": "C3",
+      "name": "HC900 C3 Controller",
+      "controllerIp": "192.168.0.230",
+      "controllerPort": 502,
+      "grpcPort": 50051,
+      "pollIntervalMs": 1000,
+      "registerMapPath": "/home/windpacer/projects/hc900_ax/docs/register-map.json",
+      "enabled": true
+    }
+  ]
+}