Init world. Basic registry API server

Work in progress .
This commit adds the core registry service implementation with methods to:
- Retrieve all registry entries
- List entries with cursor-based pagination
- Fetch specific server details by ID

Dockerfile

@@ -0,0 +1,11 @@
+FROM golang:1.23-alpine AS builder
+WORKDIR /app
+COPY . .
+RUN go build -o /build/registry ./cmd/registry
+
+FROM alpine:latest
+WORKDIR /app
+COPY --from=builder /build/registry .
+EXPOSE 8080
+
+CMD ["./registry"]