Replace log package with slog for structured logging and improve error handling

internal/config/config.go

@@ -1,7 +1,7 @@
 package config
 
 import (
-	"log"
+	"log/slog"
 	"os"
 
 	"github.com/joho/godotenv"
@@ -22,7 +22,7 @@ var Config *config
 func Load() *config {
 	err := godotenv.Load()
 	if err != nil {
-		log.Fatal("Error loading .env file")
+		panic("Error loading .env file")
 	}
 
 	// Get mastodon instance
@@ -38,23 +38,23 @@ func Load() *config {
 	// Get admin password (Its a single user/admin app so its just fine)
 	adminPassword := os.Getenv("CAOM_ADMIN_PASSWORD")
 	if adminPassword == "" {
-		log.Println("No admin password provided, using default password 'catsaregood'")
+		slog.Error("No admin password provided, using default password 'catsaregood'")
 		adminPassword = "catsaregood"
 	}
 
 	// Jwt params
 	secret := os.Getenv("CAOM_JWT_SECRET")
 	if secret == "" {
-		log.Fatal("No jwt secret provided")
+		panic("No jwt secret provided")
 	}
 	issuer := os.Getenv("CAOM_JWT_ISSUER")
 	if issuer == "" {
-		log.Println("No jwt issuer provided, using default issuer 'CatsOfMastodonBotGo'")
+		slog.Info("No jwt issuer provided, using default issuer 'CatsOfMastodonBotGo'")
 		issuer = "CatsOfMastodonBotGo"
 	}
 	audience := os.Getenv("CAOM_JWT_AUDIENCE")
 	if audience == "" {
-		log.Println("No jwt audience provided, using default audience 'CatsOfMastodonBotGo'")
+		slog.Info("No jwt audience provided, using default audience 'CatsOfMastodonBotGo'")
 		audience = "CatsOfMastodonBotGo"
 	}