NOSSUE - Add Seperate Client Service (#1715)

* initial commit
* move clients to jackc/pgx/v5/pgconn
* add clients prefix to all clients URLs
* fix makepolicy handler
* add clients prefix on proxy

Signed-off-by: b1ackd0t <blackd0t@protonmail.com>

Makefile

@@ -3,7 +3,7 @@
 
 MF_DOCKER_IMAGE_NAME_PREFIX ?= mainflux
 BUILD_DIR = build
-SERVICES = users things http coap ws lora influxdb-writer influxdb-reader mongodb-writer \
+SERVICES = clients users things http coap ws lora influxdb-writer influxdb-reader mongodb-writer \
 	mongodb-reader cassandra-writer cassandra-reader postgres-writer postgres-reader timescale-writer timescale-reader cli \
 	bootstrap opcua auth twins mqtt provision certs smtp-notifier smpp-notifier
 DOCKERS = $(addprefix docker_,$(SERVICES))
@@ -78,6 +78,7 @@ test:
 
 proto:
 	protoc -I. --go_out=. --go_opt=paths=source_relative pkg/messaging/*.proto
+	protoc -I. --go_out=. --go_opt=paths=source_relative --go-grpc_out=. --go-grpc_opt=paths=source_relative clients/policies/*.proto
 	protoc -I. --go_out=. --go_opt=paths=source_relative --go-grpc_out=. --go-grpc_opt=paths=source_relative *.proto
 
 $(SERVICES):