Project structure refactor:

- Change package name general_server to gateway
- Changing the structure of directories and packages
- Adding vendor to the project

vendor/github.com/sagikazarmark/locafero/justfile

@@ -0,0 +1,14 @@
+default:
+    just --list
+
+test:
+    go test -race -v ./...
+
+fuzz:
+    go test -race -v -fuzz=Fuzz -fuzztime=60s ./...
+
+lint:
+    golangci-lint run
+
+fmt:
+    golangci-lint fmt