feat: add Delve debugger support and update entrypoint for debugging

Dockerfile

@@ -34,6 +34,9 @@ WORKDIR /app/backend
 # Install build dependencies
 RUN apk add --no-cache gcc musl-dev sqlite-dev
 
+# Install Delve so we can attach during debugging
+RUN go install github.com/go-delve/delve/cmd/dlv@v1.22.0
+
 # Copy Go module files
 COPY backend/go.mod backend/go.sum ./
 RUN go mod download
@@ -64,6 +67,7 @@ RUN apk --no-cache add ca-certificates sqlite-libs \
 
 # Copy Go binary from backend builder
 COPY --from=backend-builder /app/backend/cpmp /app/cpmp
+COPY --from=backend-builder /go/bin/dlv /usr/local/bin/dlv
 
 # Copy frontend build from frontend builder
 COPY --from=frontend-builder /app/frontend/dist /app/frontend/dist

docker-entrypoint.sh

@@ -27,11 +27,15 @@ done
 
 # Start CPM+ management application
 echo "Starting CPM+ management application..."
-/app/cpmp &
+if [ "$CPMP_DEBUG" = "1" ]; then
+    DEBUG_PORT=${CPMP_DEBUG_PORT:-2345}
+    echo "Running CPM+ under Delve (port $DEBUG_PORT)"
+    /usr/local/bin/dlv exec /app/cpmp --headless --listen=":$DEBUG_PORT" --api-version=2 --accept-multiclient --log -- &
+else
+    /app/cpmp &
+fi
 APP_PID=$!
 echo "CPM+ started (PID: $APP_PID)"
-
-# Function to handle shutdown gracefully
 shutdown() {
     echo "Shutting down..."
     kill -TERM "$APP_PID" 2>/dev/null || true

docs/debugging-local-container.md

@@ -0,0 +1,24 @@
+# Debugging the Local Docker Image
+
+Use the `cpmp:local` image as the source of truth and attach VS Code debuggers directly to the running container.
+
+## 1. Enable the debugger
+The image now ships with the Delve debugger. When you start the container, set `CPMP_DEBUG=1` (and optionally `CPMP_DEBUG_PORT`) so CPM+ runs under Delve.
+
+```bash
+docker run --rm -it \
+  --name cpmp-debug \
+  -p 8080:8080 \
+  -p 2345:2345 \
+  -e CPM_ENV=development \
+  -e CPM_DEBUG=1 \
+  cpmp:local
+```
+
+Delve will listen on `localhost:2345`, while the UI remains available at `http://localhost:8080`.
+
+## 2. Attach VS Code
+- Use the **Attach to CPMP backend** configuration in `.vscode/launch.json` to connect the Go debugger to Delve.
+- Use the **Open CPMP frontend** configuration to launch Chrome against the management UI.
+
+These launch configurations assume the ports above are exposed. If you need a different port, set `CPMP_DEBUG_PORT` when running the container and update the Go configuration's `port` field accordingly.