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/gen/_template/encode_tdlib.tmpl

@@ -0,0 +1,75 @@
+{{- /*gotype: go.mau.fi/mautrix-telegram/pkg/gotd/gen.structDef*/ -}}
+{{ define "encode_tdlib_json" }}{{ $s := . }}
+// EncodeTDLibJSON implements tdjson.TDLibEncoder.
+func ({{ $s.Receiver }} *{{ $s.Name }}) EncodeTDLibJSON({{ $s.BufArg }} tdjson.Encoder) error {
+    if {{ $s.Receiver }} == nil {
+        return fmt.Errorf("can't encode {{ $s.RawType }} as nil")
+    }
+    {{ $s.BufArg }}.ObjStart()
+    {{ $s.BufArg }}.PutID("{{ $s.RawName }}")
+    {{ $s.BufArg }}.Comma()
+{{- if hasFlags $s }}
+    {{ $s.Receiver }}.SetFlags()
+{{- end }}
+{{- range $i, $f := $s.Fields }}
+    {{- if not $f.ConditionalBool }}
+    {{- if $f.Conditional }}
+    if {{ $s.Receiver }}.{{ $f.ConditionalField }}.Has({{ $f.ConditionalIndex }}) {
+    {{- end }}
+    {{ $s.BufArg }}.FieldStart("{{ $f.RawName }}")
+    {{- if $f.Vector }}
+    {{ $s.BufArg }}.ArrStart()
+    for {{ if $f.Encoder }}idx{{ else }}_{{ end }}, {{- if $f.DoubleVector }}row{{else}}v{{end}} := range {{ $s.Receiver }}.{{ $f.Name }} {
+    {{- if $f.DoubleVector }}
+        {{ $s.BufArg }}.ArrStart()
+        for _, v := range row {
+    {{- end }}
+    {{- if $f.Encoder }}
+        {{- if $f.Interface }}
+            if v == nil {
+            return fmt.Errorf("unable to encode {{ $s.RawType }}: field {{ $f.RawName }} element with index %d is nil", idx)
+            }
+        {{- end }}
+        if err := v.EncodeTDLibJSON({{ $s.BufArg }}); err != nil {
+            return fmt.Errorf("unable to encode {{ $s.RawType }}: field {{ $f.RawName }} element with index %d: %w", idx, err)
+        }
+    {{- else }}
+        {{ $s.BufArg }}.Put{{ $f.Func }}(v)
+    {{- end }}
+    {{ $s.BufArg }}.Comma()
+    {{- if $f.DoubleVector }}
+        }
+        {{ $s.BufArg }}.StripComma()
+        {{ $s.BufArg }}.ArrEnd()
+        {{ $s.BufArg }}.Comma()
+    {{- end }}
+    }
+    {{ $s.BufArg }}.StripComma()
+    {{ $s.BufArg }}.ArrEnd()
+    {{- else }}
+    {{- if $f.Encoder }}
+    {{- if $f.Interface }}
+    if {{ $s.Receiver }}.{{ $f.Name }} == nil {
+        return fmt.Errorf("unable to encode {{ $s.RawType }}: field {{ $f.RawName }} is nil")
+    }
+    {{- end }}
+        {{- if not (eq $f.Type "bin.Fields") }}
+        if err := {{ $s.Receiver }}.{{ $f.Name }}.EncodeTDLibJSON({{ $s.BufArg }}); err != nil {
+            return fmt.Errorf("unable to encode {{ $s.RawType }}: field {{ $f.RawName }}: %w", err)
+        }
+        {{- end }}
+    {{- else }}
+    {{ $s.BufArg }}.Put{{ $f.Func }}({{ $s.Receiver }}.{{ $f.Name }})
+    {{- end }}
+    {{- end }}
+    {{- if $f.Conditional }}
+    }
+    {{- end }}
+    {{- end }}
+    {{ $s.BufArg }}.Comma()
+{{- end }}
+    {{ $s.BufArg }}.StripComma()
+    {{ $s.BufArg }}.ObjEnd()
+    return nil
+}
+{{ end }}