Replace all log.Println and fmt.Printf with Zap structured logging

internal/backend/characters.go

@@ -1,21 +1,22 @@
 package backend
 
 import (
-	"fmt"
-	"log"
 	"os"
 	"strings"
+
+	"music-server/internal/logging"
+	"go.uber.org/zap"
 )
 
 func GetCharacterList() []string {
 	charactersPath := os.Getenv("CHARACTERS_PATH")
-	fmt.Printf("dir: %s\n", charactersPath)
+	logging.GetLogger().Debug("Getting character list", zap.String("path", charactersPath))
 	if !strings.HasSuffix(charactersPath, "/") {
 		charactersPath += "/"
 	}
 	files, err := os.ReadDir(charactersPath)
 	if err != nil {
-		log.Fatal(err)
+		logging.GetLogger().Fatal("Failed to read characters directory", zap.String("path", charactersPath), zap.String("error", err.Error()))
 	}
 
 	var characters []string
@@ -29,7 +30,7 @@ func GetCharacterList() []string {
 
 func GetCharacter(character string) string {
 	charactersPath := os.Getenv("CHARACTERS_PATH")
-	fmt.Printf("dir: %s\n", charactersPath)
+	logging.GetLogger().Debug("Getting character", zap.String("character", character), zap.String("path", charactersPath))
 	if !strings.HasSuffix(charactersPath, "/") {
 		charactersPath += "/"
 	}