Fix P2 SaaS compilation: wire dispatchNotifications correctly, add P1/P2 Dockerfiles

- P2 processor: use correct dispatchNotifications signature (channels, notification, severity)
- P2 processor: pass pool to withTenant, fix implicit any types
- P1 Dockerfile: multi-stage Rust build for proxy/api/worker binaries
- P2 agent Dockerfile: multi-stage Go build
- P2 SaaS package-lock.json generated
- All 6 products now compile cleanly

products/02-iac-drift-detection/agent/Dockerfile

@@ -1,13 +1,12 @@
-# --- Build stage ---
+# P2: dd0c/drift agent — Go binary
 FROM golang:1.22-alpine AS builder
 WORKDIR /app
-COPY go.mod go.sum ./
+COPY go.mod go.sum* ./
 RUN go mod download
 COPY . .
-RUN CGO_ENABLED=0 GOOS=linux go build -o /drift ./cmd/drift
+RUN CGO_ENABLED=0 go build -o dd0c-drift ./cmd/main.go
 
-# --- Runtime stage ---
-FROM alpine:3.19
+FROM alpine:3.20
 RUN apk add --no-cache ca-certificates
-COPY --from=builder /drift /usr/local/bin/drift
-ENTRYPOINT ["drift"]
+COPY --from=builder /app/dd0c-drift /usr/local/bin/
+ENTRYPOINT ["dd0c-drift"]