fix: harden channel rights and sticker compatibility

Co-authored-by: HSgram <3013954224@qq.com>

internal/rpc/stickers.go

@@ -102,17 +102,11 @@ func (r *Router) onMessagesGetStickerSet(ctx context.Context, req *tg.MessagesGe
 					zap.Int("documents", len(fallbackDocs)),
 				)
 			}
-			if req.Hash != 0 && req.Hash == fallbackSet.Hash {
-				return &tg.MessagesStickerSetNotModified{}, nil
-			}
 			return tgMessagesStickerSet(fallbackSet, fallbackDocs), nil
 		}
 		// 未 seed 的系统集 / 未知短名：回退兼容 stub，避免破坏客户端。
 		return tdesktop.StickerSet(req), nil
 	}
-	if req.Hash != 0 && req.Hash == set.Hash {
-		return &tg.MessagesStickerSetNotModified{}, nil
-	}
 	set, err = r.stickerSetWithViewerInstallState(ctx, set)
 	if err != nil {
 		return nil, err
@@ -191,6 +185,43 @@ func (r *Router) onMessagesGetEmojiStickers(ctx context.Context, hash int64) (tg
 	return r.allStickersForKind(ctx, hash, domain.StickerSetKindEmoji)
 }
 
+func (r *Router) onMessagesGetEmojiStickerGroups(ctx context.Context, hash int) (tg.MessagesEmojiGroupsClass, error) {
+	empty := func() tg.MessagesEmojiGroupsClass {
+		return &tg.MessagesEmojiGroups{Hash: 0, Groups: []tg.EmojiGroupClass{}}
+	}
+	if r.deps.Files == nil {
+		return empty(), nil
+	}
+	sets := r.stickerCatalogSets(ctx, domain.StickerSetKindEmoji)
+	visible := make([]domain.StickerSet, 0, len(sets))
+	for _, set := range sets {
+		if set.ID == 0 || set.Archived {
+			continue
+		}
+		visible = append(visible, set)
+	}
+	if len(visible) == 0 {
+		return empty(), nil
+	}
+	catalogHash := emojiStickerGroupsHash(visible)
+	if hash != 0 && hash == catalogHash {
+		return &tg.MessagesEmojiGroupsNotModified{}, nil
+	}
+	iconEmojiID := emojiStickerGroupIconID(visible)
+	if iconEmojiID == 0 {
+		return empty(), nil
+	}
+	return &tg.MessagesEmojiGroups{
+		Hash: catalogHash,
+		Groups: []tg.EmojiGroupClass{
+			&tg.EmojiGroupPremium{
+				Title:       "Premium",
+				IconEmojiID: iconEmojiID,
+			},
+		},
+	}, nil
+}
+
 func (r *Router) onMessagesGetMaskStickers(ctx context.Context, hash int64) (tg.MessagesAllStickersClass, error) {
 	return r.allStickersForKind(ctx, hash, domain.StickerSetKindMasks)
 }
@@ -329,6 +360,13 @@ func (r *Router) onMessagesGetFeaturedEmojiStickers(ctx context.Context, hash in
 	return r.featuredStickersForKind(ctx, hash, domain.StickerSetKindEmoji)
 }
 
+func (r *Router) onMessagesGetOldFeaturedStickers(ctx context.Context, req *tg.MessagesGetOldFeaturedStickersRequest) (tg.MessagesFeaturedStickersClass, error) {
+	if req == nil {
+		return r.onMessagesGetFeaturedStickers(ctx, 0)
+	}
+	return r.onMessagesGetFeaturedStickers(ctx, req.Hash)
+}
+
 // featuredStickersForKind 把已 seed 的（未归档）贴纸/emoji 集作为 trending 呈现。
 // 性能：先用集目录 hash 比对，命中即返回 *NotModified——封面文档解析只在 cache-miss
 // 时发生（一次批量 GetDocuments），避免每次请求都解析封面。
@@ -467,6 +505,31 @@ func featuredStickerSetsHash(sets []domain.StickerSet) int64 {
 	return int64(tdesktopCountHash(values))
 }
 
+func emojiStickerGroupsHash(sets []domain.StickerSet) int {
+	values := make([]int64, 0, len(sets)*2)
+	for _, set := range sets {
+		if set.ID == 0 || set.Archived {
+			continue
+		}
+		values = append(values, set.ID, int64(set.Hash))
+	}
+	return int(tdesktopCountHash(values) & 0x7fffffff)
+}
+
+func emojiStickerGroupIconID(sets []domain.StickerSet) int64 {
+	for _, set := range sets {
+		if set.ThumbDocumentID != 0 {
+			return set.ThumbDocumentID
+		}
+		for _, id := range set.DocumentIDs {
+			if id != 0 {
+				return id
+			}
+		}
+	}
+	return 0
+}
+
 func boolHashValue(v bool) int64 {
 	if v {
 		return 1