feat: Add linter configuration and improve error handling in download functions

.golangci.yml

@@ -0,0 +1,28 @@
+version: 2
+
+linters:
+  enable:
+    - errcheck
+    - govet
+    - staticcheck
+    - unused
+
+issues:
+  exclude-rules:
+    - path: _test\.go
+      linters:
+        - errcheck
+    - path: examples/
+      linters:
+        - errcheck
+        - unused
+
+run:
+  timeout: 5m
+  tests: true
+
+output:
+  format: colored-line-number
+  print-issued-lines: true
+  print-linter-name: true
+  sort-results: true

client.go

@@ -249,7 +249,7 @@ func (c *Client) downloadWithBasicAuth(ctx context.Context, downloadURL string)
 	if err != nil {
 		return nil, fmt.Errorf("download request failed: %w", err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
 
 	if resp.StatusCode != http.StatusOK {
 		bodyPreview, _ := io.ReadAll(resp.Body)
@@ -328,7 +328,7 @@ func (c *Client) downloadWithDigestAuth(ctx context.Context, downloadURL string)
 	if err != nil {
 		return nil, fmt.Errorf("digest auth request failed: %w", err)
 	}
-	defer resp.Body.Close()
+	defer func() { _ = resp.Body.Close() }()
 
 	if resp.StatusCode != http.StatusOK {
 		bodyPreview, _ := io.ReadAll(resp.Body)

cmd/onvif-cli/main.go

@@ -610,7 +610,7 @@ func (c *CLI) tryRTSPConnection(streamURI string) map[string]interface{} {
 	// Try to connect
 	conn, err := net.DialTimeout("tcp", hostPort, 3*time.Second)
 	if err == nil {
-		conn.Close()
+		_ = conn.Close() // Ignore error on close for connectivity check
 		details["reachable"] = true
 		details["port"] = strings.Split(hostPort, ":")[1]
 		return details