fix: errcheck lint in progress_test.go, add make lint/check targets

- Fix unchecked io.Copy return in progress_test.go (errcheck)
- Add 'make lint' target (auto-installs golangci-lint if missing)
- Add 'make check' target (runs tests + lint together)
- Update 'make test' to include -race -count=1 -timeout 120s

Author: dmitriimaksimovdevelop

Makefile

@@ -1,5 +1,5 @@
 
-.PHONY: all build clean generate test test-integration test-validation
+.PHONY: all build clean generate test test-integration test-validation lint check
 
 all: build
 
@@ -15,7 +15,14 @@ generate:
 		-c internal/ebpf/c/tcpretrans.bpf.c -o internal/ebpf/bpf/tcpretrans.o
 
 test:
-	go test ./...
+	go test -race -count=1 -timeout 120s ./...
+
+lint:
+	@which golangci-lint > /dev/null 2>&1 || { echo "Installing golangci-lint..."; go install github.com/golangci/golangci-lint/cmd/golangci-lint@latest; }
+	golangci-lint run --timeout=5m
+
+check: test lint
+	@echo "All checks passed."
 
 test-integration:
 	bash tests/integration/docker_test.sh

internal/output/progress_test.go

@@ -19,7 +19,7 @@ func captureStderr(fn func()) string {
 	os.Stderr = old
 
 	var buf bytes.Buffer
-	io.Copy(&buf, r)
+	_, _ = io.Copy(&buf, r)
 	return buf.String()
 }