plan: web previews for channels (#7022)

* plan: web previews for channels

* types for recipient side to support channel web previews and domain names

* fix

* migrations

* update schema and api types

* update schema

* rename migrations

* core: check member role

---------

Co-authored-by: Evgeny @ SimpleX Chat <259188159+evgeny-simplex@users.noreply.github.com>

packages/simplex-chat-python/src/simplex_chat/types/_types.py

@@ -1949,6 +1949,7 @@ class GroupRelay(TypedDict):
     userChatRelay: "UserChatRelay"
     relayStatus: "RelayStatus"
     relayLink: NotRequired[str]
+    relayCap: "RelayCapabilities"
 
 class GroupRootKey_private(TypedDict):
     type: Literal["private"]
@@ -2356,6 +2357,12 @@ ProxyError = ProxyError_PROTOCOL | ProxyError_BROKER | ProxyError_BASIC_AUTH | P
 
 ProxyError_Tag = Literal["PROTOCOL", "BROKER", "BASIC_AUTH", "NO_SESSION"]
 
+class PublicGroupAccess(TypedDict):
+    groupWebPage: NotRequired[str]
+    groupDomain: NotRequired[str]
+    domainWebPage: bool
+    allowEmbedding: bool
+
 class PublicGroupData(TypedDict):
     publicMemberCount: int  # int64
 
@@ -2363,6 +2370,7 @@ class PublicGroupProfile(TypedDict):
     groupType: "GroupType"
     groupLink: str
     publicGroupId: str
+    publicGroupAccess: NotRequired["PublicGroupAccess"]
 
 class RCErrorType_internal(TypedDict):
     type: Literal["internal"]
@@ -2631,6 +2639,9 @@ RcvMsgError = RcvMsgError_dropped | RcvMsgError_parseError
 
 RcvMsgError_Tag = Literal["dropped", "parseError"]
 
+class RelayCapabilities(TypedDict):
+    baseWebUrl: NotRequired[str]
+
 class RelayProfile(TypedDict):
     displayName: str
     fullName: str