feat(images): cache lifetime in config

internal/pkg/config/default.go

@@ -1,10 +1,13 @@
 package config
 
+import "time"
+
 func Default() Cfg {
 	return Cfg{
 		Image: &ImageConfig{
-			Concurency: 10,
-			Quality:    80,
+			Concurency:    10,
+			Quality:       80,
+			CacheLifetime: time.Hour * 24 * 31,
 		},
 		Tracking: &UmamiConfig{
 			ScriptSrc: "https://umami.schreifuchs.ch/script.js",

internal/pkg/config/resource.go

@@ -3,6 +3,7 @@ package config
 import (
 	"context"
 	"log/slog"
+	"time"
 
 	"github.com/sethvargo/go-envconfig"
 )
@@ -36,8 +37,9 @@ type ValkeyConfig struct {
 }
 
 type ImageConfig struct {
-	Concurency int64 `env:"CONCURENCY"`
-	Quality    int   `env:"QUALITY"`
+	Concurency    int64         `env:"CONCURENCY"`
+	Quality       int           `env:"QUALITY"`
+	CacheLifetime time.Duration `env:"CACHE_LIFETIME"`
 }
 
 type UmamiConfig struct {
@@ -54,6 +56,7 @@ func Read(ctx context.Context) (cfg Cfg, err error) {
 		// overridden.
 		DefaultDelimiter: ";",
 		DefaultSeparator: "@",
+		DefaultOverwrite: true,
 
 		Lookuper: envconfig.MultiLookuper(secretLookuper(), envconfig.OsLookuper()),
 	})