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/peers/errors.go

@@ -0,0 +1,27 @@
+package peers
+
+import (
+	"fmt"
+
+	"go.mau.fi/mautrix-telegram/pkg/gotd/tg"
+)
+
+// PhoneNotFoundError is returned when Manager unable to find contact with given phone.
+type PhoneNotFoundError struct {
+	Phone string
+}
+
+// Error implements error.
+func (c *PhoneNotFoundError) Error() string {
+	return "contact not found"
+}
+
+// PeerNotFoundError is returned when Manager unable to find Peer with given tg.PeerClass.
+type PeerNotFoundError struct {
+	Peer tg.PeerClass
+}
+
+// Error implements error.
+func (p *PeerNotFoundError) Error() string {
+	return fmt.Sprintf("can't resolve %v", p.Peer)
+}