move gotd fork into repo. (#111)

- update to latest telegram layer
- remove some references to fields in tg.Entities that don't exist in
the schema
- originally added here:
https://github.com/beeper/td/commit/820929062a2ba0104397bc01235ab58a9cff780e
  - referenced here
-
https://github.com/mautrix/telegramgo/commit/124f0967ed195b5a380c9bd02e170ada9710dde3
-
https://github.com/mautrix/telegramgo/commit/4205047aab2e0639217148b5d125bfaab668bd8e

pkg/gotd/telegram/message/styling/builder.go

@@ -0,0 +1,34 @@
+package styling
+
+import (
+	"github.com/go-faster/errors"
+
+	"go.mau.fi/mautrix-telegram/pkg/gotd/telegram/message/entity"
+)
+
+type textBuilder struct {
+	*entity.Builder
+}
+
+func (b *textBuilder) Perform(texts ...StyledTextOption) error {
+	b.GrowEntities(len(texts))
+	var length int
+	for i := range texts {
+		length += texts[i].size
+	}
+	b.GrowText(length)
+
+	for idx, opt := range texts {
+		if err := opt.perform(b); err != nil {
+			return errors.Wrapf(err, "perform %d styling option", idx+2)
+		}
+	}
+
+	return nil
+}
+
+// Perform performs all options to the given builder.
+func Perform(builder *entity.Builder, texts ...StyledTextOption) error {
+	tb := &textBuilder{Builder: builder}
+	return tb.Perform(texts...)
+}