Initial commit of Descrybe v2 without local scratch artifacts.

Drop one-shot tmp/axe scripts and agent i18n scratch so the Gitea tree is deployable.

apps/api/internal/feeds/errors.go

@@ -0,0 +1,59 @@
+package feeds
+
+import (
+	"errors"
+
+	"github.com/jackc/pgx/v5"
+)
+
+// ErrFormatMismatch is returned when the public export URL extension does not
+// match the feed's configured format. Public HTTP handlers must map this to the
+// same opaque 404 as an unknown token (no existence oracle).
+var ErrFormatMismatch = errors.New("format mismatch")
+
+// ErrNotFound is returned when a company-scoped feed (or related row) is missing.
+var ErrNotFound = errors.New("not found")
+
+// clientError is a validation/business message safe to return to API clients.
+type clientError struct {
+	msg string
+}
+
+func (e *clientError) Error() string { return e.msg }
+
+// ClientMsg marks a message as safe to expose in HTTP 4xx responses.
+func ClientMsg(msg string) error {
+	return &clientError{msg: msg}
+}
+
+// ClientError reports whether err is a known client-facing feeds error.
+func ClientError(err error) (msg string, ok bool) {
+	if err == nil {
+		return "", false
+	}
+	var ce *clientError
+	if errors.As(err, &ce) {
+		return ce.msg, true
+	}
+	switch {
+	case errors.Is(err, ErrNotFound), errors.Is(err, pgx.ErrNoRows):
+		return "not found", true
+	case errors.Is(err, ErrFormatMismatch),
+		errors.Is(err, errURLRequired),
+		errors.Is(err, errURLScheme),
+		errors.Is(err, errURLPrivate),
+		errors.Is(err, errURLFTP),
+		errors.Is(err, errDownloadTooLarge),
+		errors.Is(err, errParseTooManyRows),
+		errors.Is(err, errSourceRequired),
+		errors.Is(err, errLocalSource):
+		return err.Error(), true
+	default:
+		return "", false
+	}
+}
+
+// IsNotFound reports whether err means a missing feed/resource.
+func IsNotFound(err error) bool {
+	return errors.Is(err, ErrNotFound) || errors.Is(err, pgx.ErrNoRows)
+}