feat: sync ephemeral transient messages

Sync telesrv 570ccf8 (feat(ephemeral): implement Layer 228 transient messages).

Skipped telesrv docs changes per public sync rules; normalized the public appearance seed label.

internal/rpc/ephemeral_rpc_test.go

@@ -0,0 +1,96 @@
+package rpc
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/iamxvbaba/td/clock"
+	"github.com/iamxvbaba/td/tg"
+	"go.uber.org/zap/zaptest"
+
+	"telesrv/internal/domain"
+	"telesrv/internal/store/memory"
+)
+
+type ephemeralReportChannels struct {
+	ChannelsService
+	view domain.ChannelView
+}
+
+func (s *ephemeralReportChannels) ResolveChannel(context.Context, int64, int64) (domain.ChannelView, error) {
+	return s.view, nil
+}
+
+type ephemeralReportService struct {
+	EphemeralService
+	target domain.EphemeralMessage
+	calls  int
+}
+
+func (s *ephemeralReportService) ReportTarget(_ context.Context, userID int64, device domain.EphemeralDevice, peer domain.Peer, id int) (domain.EphemeralMessage, error) {
+	s.calls++
+	if userID != s.target.ReceiverUserID || device.UserID != userID || device.BusinessAuthKeyID != s.target.OriginDevice.BusinessAuthKeyID ||
+		peer != s.target.Peer || id != s.target.ID {
+		return domain.EphemeralMessage{}, domain.ErrEphemeralForbidden
+	}
+	return s.target, nil
+}
+
+func TestEphemeralReportPersistsOnlyFinalIdempotentEvidence(t *testing.T) {
+	const userID int64 = 2001
+	const channelID int64 = 3001
+	now := time.Now()
+	authKey := [8]byte{1, 2, 3}
+	target := domain.EphemeralMessage{
+		ID: 77, Peer: domain.Peer{Type: domain.PeerTypeChannel, ID: channelID},
+		SenderUserID: 1001, ReceiverUserID: userID, Date: int(now.Unix()), RandomID: 78,
+		Content:      domain.EphemeralContent{Message: "abuse"},
+		OriginDevice: domain.EphemeralDevice{UserID: userID, BusinessAuthKeyID: authKey, SessionID: 99},
+		PayloadHash:  [32]byte{9}, Version: 1, CreatedAt: now, ExpiresAt: now.Add(domain.EphemeralMessageRetention),
+	}
+	reports := memory.NewEphemeralReportStore()
+	ephemeral := &ephemeralReportService{target: target}
+	channels := &ephemeralReportChannels{view: domain.ChannelView{
+		Channel: domain.Channel{ID: channelID, AccessHash: 42, Megagroup: true},
+		Self:    domain.ChannelMember{ChannelID: channelID, UserID: userID, Status: domain.ChannelMemberActive},
+	}}
+	router := New(Config{}, Deps{Ephemeral: ephemeral, EphemeralReports: reports, Channels: channels}, zaptest.NewLogger(t), clock.System)
+	ctx := WithSessionID(WithAuthKeyID(WithUserID(context.Background(), userID), authKey), 99)
+	request := &tg.EphemeralReportMessageRequest{
+		Peer: &tg.InputPeerChannel{ChannelID: channelID, AccessHash: 42}, ID: target.ID,
+	}
+
+	result, err := router.onEphemeralReportMessage(ctx, request)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, ok := result.(*tg.ReportResultChooseOption); !ok || len(reports.Reports()) != 0 {
+		t.Fatalf("initial result=%T reports=%+v", result, reports.Reports())
+	}
+	request.Option = []byte("other")
+	result, err = router.onEphemeralReportMessage(ctx, request)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, ok := result.(*tg.ReportResultAddComment); !ok || len(reports.Reports()) != 0 {
+		t.Fatalf("comment result=%T reports=%+v", result, reports.Reports())
+	}
+	request.Option, request.Message = []byte("spam"), "evidence comment"
+	for range 2 {
+		result, err = router.onEphemeralReportMessage(ctx, request)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if _, ok := result.(*tg.ReportResultReported); !ok {
+			t.Fatalf("final result=%T", result)
+		}
+	}
+	stored := reports.Reports()
+	if len(stored) != 1 || stored[0].Evidence.Content.Message != "abuse" || stored[0].Comment != "evidence comment" {
+		t.Fatalf("reports=%+v", stored)
+	}
+	if ephemeral.calls != 4 {
+		t.Fatalf("ReportTarget calls=%d", ephemeral.calls)
+	}
+}