Fix golangci-lint errcheck and unused errors

- manager.go: add _ = to syscall.Kill and proc.Signal calls (6 fixes)
- chat.go: add _ = to c.Writer.WriteString calls (9 fixes)
- webhook.go: remove unused webhookSecret field

internal/api/handlers/chat.go

@@ -180,19 +180,19 @@ func (h *ChatHandler) handleStream(c *gin.Context, apiKey *db.ApiKey, req ChatCo
 			completionTokens += len(resp.Choices[0].Delta.Content) / 4
 
 			// Write SSE
-			c.Writer.WriteString("data: ")
-			c.Writer.WriteString("{\"id\":\"chatcmpl-1\",\"object\":\"chat.completion.chunk\",\"created\":")
-			c.Writer.WriteString(formatInt(resp.Created))
-			c.Writer.WriteString(",\"model\":\"")
-			c.Writer.WriteString(resp.Model)
-			c.Writer.WriteString("\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"")
-			c.Writer.WriteString(escapeJSON(resp.Choices[0].Delta.Content))
-			c.Writer.WriteString("\"}}]}\n\n")
+			_, _ = c.Writer.WriteString("data: ")
+			_, _ = c.Writer.WriteString("{\"id\":\"chatcmpl-1\",\"object\":\"chat.completion.chunk\",\"created\":")
+			_, _ = c.Writer.WriteString(formatInt(resp.Created))
+			_, _ = c.Writer.WriteString(",\"model\":\"")
+			_, _ = c.Writer.WriteString(resp.Model)
+			_, _ = c.Writer.WriteString("\",\"choices\":[{\"index\":0,\"delta\":{\"content\":\"")
+			_, _ = c.Writer.WriteString(escapeJSON(resp.Choices[0].Delta.Content))
+			_, _ = c.Writer.WriteString("\"}}]}\n\n")
 			flusher.Flush()
 
 		case err := <-errCh:
 			h.logUsage(c, apiKey, req.Model, promptTokens, completionTokens, totalTokens, "error", start)
-			c.Writer.WriteString("data: [DONE]\n\n")
+			_, _ = c.Writer.WriteString("data: [DONE]\n\n")
 			flusher.Flush()
 			if err != nil {
 				slog.Error("stream error", "error", err)

internal/llama/manager.go

@@ -92,14 +92,14 @@ func (m *Manager) Stop() {
 
 		pgid, err := syscall.Getpgid(m.proc.Process.Pid)
 		if err == nil {
-			syscall.Kill(-pgid, syscall.SIGTERM)
+			_ = syscall.Kill(-pgid, syscall.SIGTERM)
 		} else {
-			m.proc.Process.Signal(syscall.SIGTERM)
+			_ = m.proc.Process.Signal(syscall.SIGTERM)
 		}
 
 		<-ctx.Done()
 		if m.proc.ProcessState == nil {
-			syscall.Kill(-pgid, syscall.SIGKILL)
+			_ = syscall.Kill(-pgid, syscall.SIGKILL)
 		}
 	}
 
@@ -256,9 +256,9 @@ func (m *Manager) terminateProcess() {
 
 	pgid, err := syscall.Getpgid(m.proc.Process.Pid)
 	if err == nil {
-		syscall.Kill(-pgid, syscall.SIGTERM)
+		_ = syscall.Kill(-pgid, syscall.SIGTERM)
 	} else {
-		m.proc.Process.Signal(syscall.SIGTERM)
+		_ = m.proc.Process.Signal(syscall.SIGTERM)
 	}
 
 	done := make(chan error, 1)
@@ -269,7 +269,7 @@ func (m *Manager) terminateProcess() {
 	select {
 	case <-ctx.Done():
 		if pgid, err := syscall.Getpgid(m.proc.Process.Pid); err == nil {
-			syscall.Kill(-pgid, syscall.SIGKILL)
+			_ = syscall.Kill(-pgid, syscall.SIGKILL)
 		}
 	case <-done:
 	}

internal/quota/webhook.go

@@ -32,7 +32,6 @@ type WebhookPayload struct {
 type WebhookService struct {
 	db     *gorm.DB
 	client *http.Client
-	webhookSecret string
 }
 
 func NewWebhookService(db *gorm.DB) *WebhookService {