Refactor Docker and Makefile configurations for improved build processes

- Updated docker-compose.tools.yml to mount source code at /src and set working directory for backend tools, ensuring proper Go module caching.
- Modified Dockerfile.tools to install the latest golangci-lint version compatible with Go 1.24 and adjusted working directory for build-time operations.
- Enhanced Makefile to build backend tools before running tests and linting, ensuring dependencies are up-to-date and improving overall workflow efficiency.
- Refactored test and handler files to include error handling for database operations, enhancing reliability and debugging capabilities.

internal/app/handlers/client.go

@@ -66,7 +66,7 @@ func (h *Handlers) clientLocate(rw http.ResponseWriter, req *http.Request) {
 	}
 	rw.Header().Set("Content-Type", "text/plain")
 	rw.WriteHeader(http.StatusOK)
-	rw.Write([]byte(result))
+	_, _ = rw.Write([]byte(result))
 }
 
 func (h *Handlers) clientGridUpdate(rw http.ResponseWriter, req *http.Request) {
@@ -85,7 +85,7 @@ func (h *Handlers) clientGridUpdate(rw http.ResponseWriter, req *http.Request) {
 	}
 	rw.Header().Set("Content-Type", "application/json")
 	rw.WriteHeader(http.StatusOK)
-	json.NewEncoder(rw).Encode(result.Response)
+	_ = json.NewEncoder(rw).Encode(result.Response)
 }
 
 func (h *Handlers) clientGridUpload(rw http.ResponseWriter, req *http.Request) {