Implement ingest-service: MQTT -> ClickHouse (batched) + RabbitMQ event

Subscribes to devices/+/telemetry, validates payloads, buffers writes into
ClickHouse (flush on size or interval), and emits a per-reading event on
RabbitMQ for rule-engine-service to consume later. Adds the initial Postgres
and ClickHouse schema migrations, a Dockerfile, and wires the service into
docker-compose. Verified end-to-end via docker compose + mosquitto_pub: row
lands in ClickHouse and the event reaches the telemetry.new_reading queue.

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

migrations/postgres/0001_init.sql

@@ -0,0 +1,59 @@
+-- Core platform schema: users, zones, device types, devices, automation rules.
+-- Deliberately generic — no growbox-specific tables or columns. A "growbox"
+-- is just a row in zones with device_types like light/pump/fan attached to it.
+
+CREATE TABLE users (
+    id            BIGSERIAL PRIMARY KEY,
+    email         TEXT NOT NULL UNIQUE,
+    password_hash TEXT NOT NULL,
+    role          TEXT NOT NULL DEFAULT 'owner' CHECK (role IN ('owner', 'viewer')),
+    created_at    TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE TABLE zones (
+    id          BIGSERIAL PRIMARY KEY,
+    user_id     BIGINT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    name        TEXT NOT NULL,
+    description TEXT,
+    created_at  TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE TABLE device_types (
+    id           BIGSERIAL PRIMARY KEY,
+    code         TEXT NOT NULL UNIQUE, -- light, pump, fan, sensor_temp_humidity, vacuum, ...
+    category     TEXT NOT NULL CHECK (category IN ('actuator', 'sensor')),
+    capabilities JSONB NOT NULL DEFAULT '[]' -- e.g. ["turn_on","turn_off","set_level"]
+);
+
+CREATE TABLE devices (
+    id             BIGSERIAL PRIMARY KEY,
+    user_id        BIGINT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    zone_id        BIGINT NOT NULL REFERENCES zones(id) ON DELETE CASCADE,
+    device_type_id BIGINT NOT NULL REFERENCES device_types(id),
+    name           TEXT NOT NULL,
+    external_id    TEXT NOT NULL UNIQUE, -- physical device id (ESP32 chip id, etc.)
+    protocol       TEXT NOT NULL DEFAULT 'mqtt',
+    status         TEXT NOT NULL DEFAULT 'offline' CHECK (status IN ('online', 'offline')),
+    created_at     TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE INDEX devices_zone_id_idx ON devices(zone_id);
+CREATE INDEX devices_external_id_idx ON devices(external_id);
+
+CREATE TABLE automation_rules (
+    id                          BIGSERIAL PRIMARY KEY,
+    user_id                     BIGINT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    zone_id                     BIGINT NOT NULL REFERENCES zones(id) ON DELETE CASCADE,
+    target_device_id            BIGINT NOT NULL REFERENCES devices(id) ON DELETE CASCADE,
+    condition_source_device_id  BIGINT NOT NULL REFERENCES devices(id) ON DELETE CASCADE,
+    condition_sensor_type       TEXT NOT NULL,
+    condition_operator          TEXT NOT NULL CHECK (condition_operator IN ('>', '<', '>=', '<=', '=', '!=')),
+    condition_value             DOUBLE PRECISION NOT NULL,
+    action_type                 TEXT NOT NULL, -- e.g. turn_on, turn_off, set_level
+    action_params               JSONB NOT NULL DEFAULT '{}',
+    is_active                   BOOLEAN NOT NULL DEFAULT true,
+    created_at                  TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE INDEX automation_rules_zone_id_idx ON automation_rules(zone_id);
+CREATE INDEX automation_rules_active_idx ON automation_rules(is_active) WHERE is_active;