feat: Implement graceful server shutdown, optimize WASM module instantiation, remove tokenizer files, and refine config saving and admin key warning.

cmd/ds2api/main.go

@@ -1,9 +1,13 @@
 package main
 
 import (
+	"context"
 	"net/http"
 	"os"
+	"os/signal"
 	"strings"
+	"syscall"
+	"time"
 
 	"ds2api/internal/config"
 	"ds2api/internal/server"
@@ -17,9 +21,34 @@ func main() {
 	if port == "" {
 		port = "5001"
 	}
-	config.Logger.Info("starting ds2api", "port", port)
-	if err := http.ListenAndServe("0.0.0.0:"+port, app.Router); err != nil {
-		config.Logger.Error("server stopped", "error", err)
+
+	srv := &http.Server{
+		Addr:    "0.0.0.0:" + port,
+		Handler: app.Router,
+	}
+
+	// Start server in a goroutine so we can listen for shutdown signals.
+	go func() {
+		config.Logger.Info("starting ds2api", "port", port)
+		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			config.Logger.Error("server stopped unexpectedly", "error", err)
+			os.Exit(1)
+		}
+	}()
+
+	// Wait for interrupt signal (Ctrl+C / SIGTERM).
+	quit := make(chan os.Signal, 1)
+	signal.Notify(quit, os.Interrupt, syscall.SIGTERM)
+	sig := <-quit
+	config.Logger.Info("shutdown signal received", "signal", sig.String())
+
+	// Graceful shutdown: allow up to 10 seconds for in-flight requests to complete.
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	if err := srv.Shutdown(ctx); err != nil {
+		config.Logger.Error("graceful shutdown failed, forcing exit", "error", err)
 		os.Exit(1)
 	}
+	config.Logger.Info("server gracefully stopped")
 }