Enforce Go style rules across codebase

Apply five style rules: convert iota string enums to typed
string constants, replace errors.As with errors.AsType,
merge three-group imports into two groups, fix multiline
parameter/argument formatting, and replace fmt.Sprintf URL
construction with net/url.

Signed-off-by: Émile Ré <emile@probo.com>

pkg/server/gqlutils/errors.go

@@ -143,11 +143,9 @@ func Conflictf(ctx context.Context, format string, a ...any) *gqlerror.Error {
 }
 
 func Invalid(ctx context.Context, err error) *gqlerror.Error {
-	var errValidation *validator.ValidationError
-
 	var details map[string]any
 
-	if errors.As(err, &errValidation) {
+	if errValidation, ok := errors.AsType[*validator.ValidationError](err); ok {
 		details = map[string]any{
 			"cause": errValidation.Code,
 			"field": errValidation.Field,

pkg/server/gqlutils/handler.go

@@ -22,7 +22,6 @@ import (
 	"github.com/99designs/gqlgen/graphql/handler"
 	"github.com/99designs/gqlgen/graphql/handler/extension"
 	"github.com/99designs/gqlgen/graphql/handler/transport"
-
 	"go.gearno.de/kit/log"
 )
 

pkg/server/gqlutils/recovery.go

@@ -31,8 +31,7 @@ func RecoverFunc(ctx context.Context, err any) error {
 		return gqlErr
 	}
 
-	var errValidations validator.ValidationErrors
-	if errors.As(asError(err), &errValidations) {
+	if errValidations, ok := errors.AsType[validator.ValidationErrors](asError(err)); ok {
 		gqlErrors := gqlerror.List{}
 
 		for _, err := range errValidations {
@@ -48,9 +47,10 @@ func RecoverFunc(ctx context.Context, err any) error {
 		return gqlErrors
 	}
 
-	var permissionDeniedErr *iam.ErrInsufficientPermissions
-	if errTyped, ok := err.(error); ok && errors.As(errTyped, &permissionDeniedErr) {
-		return Forbidden(ctx, permissionDeniedErr)
+	if errTyped, ok := err.(error); ok {
+		if permissionDeniedErr, ok := errors.AsType[*iam.ErrInsufficientPermissions](errTyped); ok {
+			return Forbidden(ctx, permissionDeniedErr)
+		}
 	}
 
 	logger := httpserver.LoggerFromContext(ctx)