Scaffold repo: infra docker-compose, service layout, README

Sets up the microservice home-automation platform skeleton: docker-compose
for mosquitto/postgres/clickhouse/redis/rabbitmq, per-service README stubs
describing responsibilities, and top-level README with architecture/stack.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

services/rule-engine-service/README.md

@@ -0,0 +1,18 @@
+# rule-engine-service (Go)
+
+Status: not implemented yet.
+
+Responsibility:
+- Consume "new reading" events from RabbitMQ (async — delivery reliability
+  matters more than latency here).
+- Load active `automation_rules` for the relevant zone/device from PostgreSQL,
+  caching in memory/Redis to avoid a DB round-trip per event.
+- Evaluate rule conditions generically: `sensor_type X operator value` against
+  the reading — no hardcoded sensor/device names, everything comes from the
+  `automation_rules` row.
+- On match: call device-control-service over gRPC (needs a fast pass/fail
+  result) and publish an event to notification-service over RabbitMQ (not
+  latency-critical).
+
+Not this service's job: talking to MQTT or Redis directly — device state
+changes always go through device-control-service's gRPC API.