Added support for fetching character images from the server

internal/backend/charecters.go

@@ -0,0 +1,35 @@
+package backend
+
+import (
+	"log"
+	"os"
+	"strings"
+)
+
+func GetCharacters() []string {
+	musicPath := os.Getenv("MUSIC_PATH")
+	charactersPath := musicPath + "characters/"
+	files, err := os.ReadDir(charactersPath)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	var characters []string
+	for _, file := range files {
+		if isImage(file) {
+			characters = append(characters, file.Name())
+		}
+	}
+	return characters
+}
+
+func GetCharacter(character string) string {
+	musicPath := os.Getenv("MUSIC_PATH")
+	charactersPath := musicPath + "characters/"
+	return charactersPath + character
+}
+
+func isImage(entry os.DirEntry) bool {
+	return !entry.IsDir() && (strings.HasSuffix(entry.Name(), ".jpg") || strings.HasSuffix(entry.Name(), ".png"))
+}
+