Enhance server with context initialization and graceful shutdown

- Added context-aware server initialization in cmd/server/main.go
- Implemented graceful shutdown handling with SIGINT/SIGTERM signals
- Added 30-second shutdown timeout for active connections
- Updated Greet service to use context.Context as first parameter
- Enhanced Zerolog integration with Trace level logging
- Added context-aware logging in Greet function calls
- Fixed route structure to use /api/v1/greet/* prefix
- Updated all handlers and tests to use context
- Comprehensive AGENTS.md documentation with verified commands
- Added server context management architecture section
- Updated API endpoint documentation with working examples

Changes:
- cmd/server/main.go: Complete rewrite with context and graceful shutdown
- pkg/greet/greet.go: Added context parameter and trace logging
- pkg/greet/api_v1.go: Updated interface and handlers for context
- pkg/greet/greet_test.go: Updated tests to use context
- cmd/greet/main.go: Updated CLI to use context
- pkg/server/server.go: Trace level config and context logging
- AGENTS.md: Comprehensive documentation update
- go.mod/go.sum: Added Zerolog dependency

All tests passing, server working with graceful shutdown verified.

cmd/greet/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"fmt"
 	"os"
 
@@ -14,5 +15,5 @@ func main() {
 		name = os.Args[1]
 	}
 	
-	fmt.Println(service.Greet(name))
+	fmt.Println(service.Greet(context.Background(), name))
 }

cmd/server/main.go

@@ -1,15 +1,65 @@
 package main
 
 import (
+	"context"
 	"fmt"
 	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
 
 	"DanceLessonsCoach/pkg/server"
+	"github.com/rs/zerolog/log"
 )
 
 func main() {
-	server := server.NewServer()
+	// Create root context with cancellation
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
 
-	fmt.Println("Server running on :8080")
-	http.ListenAndServe(":8080", server.Router())
+	// Set up graceful shutdown
+	sigChan := make(chan os.Signal, 1)
+	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
+
+	// Start server in goroutine
+	server := server.NewServer()
+	serverCtx, serverStop := context.WithCancel(ctx)
+	
+	go func() {
+		fmt.Println("Server running on :8080")
+		log.Info().Msg("Starting HTTP server on :8080")
+		
+		srv := &http.Server{
+			Addr:    ":8080",
+			Handler: server.Router(),
+		}
+		
+		// Listen for shutdown signal
+		go func() {
+			<-sigChan
+			log.Info().Msg("Shutdown signal received")
+			
+			// Create shutdown context with timeout
+			shutdownCtx, shutdownCancel := context.WithTimeout(context.Background(), 30*time.Second)
+			defer shutdownCancel()
+			
+			if err := srv.Shutdown(shutdownCtx); err != nil {
+				log.Error().Err(err).Msg("Server shutdown failed")
+			} else {
+				log.Info().Msg("Server shutdown complete")
+			}
+			
+			cancel()
+			serverStop()
+		}()
+		
+		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			log.Error().Err(err).Msg("Server error")
+		}
+	}()
+	
+	// Wait for shutdown
+	<-serverCtx.Done()
+	log.Info().Msg("Server exited")
 }