Add Temporal worker and test client programs

Creates:
- cmd/worker/main.go: Worker that registers workflows and activities
- cmd/test-workflow/main.go: Test client to trigger workflows

Adds go.temporal.io/sdk dependency to go.mod.

cmd/test-workflow/main.go

@@ -0,0 +1,88 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"log"
+	"time"
+
+	"go.temporal.io/sdk/client"
+	"github.com/Riotpiaole/homelab-frontend/internal/workflow"
+)
+
+func main() {
+	hostPort := flag.String("host", "temporal.temporal:7233", "Temporal server host:port")
+	namespace := flag.String("namespace", "production", "Temporal namespace")
+	taskQueue := flag.String("queue", "worker-production", "Task queue")
+	workflowType := flag.String("workflow", "HelloWorldWorkflow", "Workflow type")
+	workflowID := flag.String("id", "", "Workflow ID (auto-generated if not set)")
+	flag.Parse()
+
+	// Auto-generate ID
+	if *workflowID == "" {
+		*workflowID = fmt.Sprintf("test-%s-%d", *workflowType, time.Now().Unix())
+	}
+
+	log.Printf("Connecting to Temporal at %s (namespace: %s)", *hostPort, *namespace)
+
+	// Connect to Temporal
+	c, err := client.Dial(client.Options{
+		HostPort:  *hostPort,
+		Namespace: *namespace,
+	})
+	if err != nil {
+		log.Fatalf("Failed to connect: %v", err)
+	}
+	defer c.Close()
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	// Start workflow
+	log.Printf("Starting %s (ID: %s)", *workflowType, *workflowID)
+
+	var run client.WorkflowRun
+	switch *workflowType {
+	case "HelloWorldWorkflow":
+		run, err = c.ExecuteWorkflow(ctx, client.StartWorkflowOptions{
+			ID:        *workflowID,
+			TaskQueue: *taskQueue,
+		}, workflow.HelloWorldWorkflow, "World")
+
+	case "GreeterWorkflow":
+		run, err = c.ExecuteWorkflow(ctx, client.StartWorkflowOptions{
+			ID:        *workflowID,
+			TaskQueue: *taskQueue,
+		}, workflow.GreeterWorkflow, "Alice")
+
+	case "ProcessOrderWorkflow":
+		run, err = c.ExecuteWorkflow(ctx, client.StartWorkflowOptions{
+			ID:        *workflowID,
+			TaskQueue: *taskQueue,
+		}, workflow.ProcessOrderWorkflow, "ORDER-12345")
+
+	default:
+		log.Fatalf("Unknown workflow type: %s", *workflowType)
+	}
+
+	if err != nil {
+		log.Fatalf("Failed to start workflow: %v", err)
+	}
+
+	log.Printf("✓ Workflow submitted")
+	log.Printf("  Run ID:       %s", run.GetRunID())
+	log.Printf("  Workflow ID:  %s", *workflowID)
+	log.Printf("  Watch at:     http://localhost:8080/namespaces/%s/workflows/%s", *namespace, *workflowID)
+
+	// Try to get result
+	ctx2, cancel2 := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel2()
+
+	var result string
+	if err := run.Get(ctx2, &result); err != nil {
+		log.Printf("⏳ Workflow executing (or error): %v", err)
+	} else {
+		log.Printf("✓ Result: %s", result)
+	}
+}

cmd/worker/main.go

@@ -0,0 +1,63 @@
+package main
+
+import (
+	"flag"
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"go.temporal.io/sdk/client"
+	"go.temporal.io/sdk/worker"
+	"github.com/Riotpiaole/homelab-frontend/internal/workflow"
+)
+
+func main() {
+	hostPort := flag.String("host", "temporal.temporal:7233", "Temporal server host:port")
+	namespace := flag.String("namespace", "production", "Temporal namespace")
+	taskQueue := flag.String("queue", "worker-production", "Task queue")
+	flag.Parse()
+
+	// Connect to Temporal server
+	c, err := client.Dial(client.Options{
+		HostPort:  *hostPort,
+		Namespace: *namespace,
+	})
+	if err != nil {
+		log.Fatalf("Failed to connect to Temporal: %v", err)
+	}
+	defer c.Close()
+
+	log.Printf("Connected to Temporal at %s (namespace: %s)", *hostPort, *namespace)
+
+	// Create worker
+	w := worker.New(c, *taskQueue, worker.Options{})
+
+	// Register workflows
+	w.RegisterWorkflow(workflow.HelloWorldWorkflow)
+	w.RegisterWorkflow(workflow.GreeterWorkflow)
+	w.RegisterWorkflow(workflow.ProcessOrderWorkflow)
+
+	// Register activities
+	w.RegisterActivity(workflow.GreetActivity)
+	w.RegisterActivity(workflow.ValidateOrderActivity)
+	w.RegisterActivity(workflow.ProcessPaymentActivity)
+	w.RegisterActivity(workflow.NotifyCustomerActivity)
+
+	log.Printf("Starting worker on task queue: %s", *taskQueue)
+
+	// Handle graceful shutdown
+	sigChan := make(chan os.Signal, 1)
+	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		<-sigChan
+		log.Println("Shutting down worker...")
+		w.Stop()
+	}()
+
+	// Run worker (blocks)
+	if err := w.Run(worker.InterruptCh()); err != nil {
+		log.Fatalf("Worker error: %v", err)
+	}
+}