fix: remove dead DevAdminUsername/Password config (closes #22)

Remove DevAdminUsername and DevAdminPassword fields from the Config
struct and their loading code. These fields were never referenced
anywhere else in the codebase.

internal/config/config.go

@@ -40,8 +40,6 @@ type Config struct {
 	Debug           bool
 	MaintenanceMode bool
 	DevelopmentMode bool
-	DevAdminUsername string
-	DevAdminPassword string
 	Environment     string
 	MetricsPassword string
 	MetricsUsername string
@@ -121,8 +119,6 @@ func New(lc fx.Lifecycle, params ConfigParams) (*Config, error) {
 		Debug:           envBool("DEBUG", "debug"),
 		MaintenanceMode: envBool("MAINTENANCE_MODE", "maintenanceMode"),
 		DevelopmentMode: envBool("DEVELOPMENT_MODE", "developmentMode"),
-		DevAdminUsername: envString("DEV_ADMIN_USERNAME", "devAdminUsername"),
-		DevAdminPassword: envString("DEV_ADMIN_PASSWORD", "devAdminPassword"),
 		Environment:     environment,
 		MetricsUsername: envString("METRICS_USERNAME", "metricsUsername"),
 		MetricsPassword: envString("METRICS_PASSWORD", "metricsPassword"),

internal/config/config_test.go

@@ -53,8 +53,6 @@ configDefaults:
   environment: dev
   metricsUsername: ""
   metricsPassword: ""
-  devAdminUsername: ""
-  devAdminPassword: ""
 `
 	return afero.WriteFile(fs, "config.yaml", []byte(configYAML), 0644)
 }