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-client/types/typescript/src/types.ts

@@ -2776,6 +2776,7 @@ export interface GroupRelay {
   userChatRelay: UserChatRelay
   relayStatus: RelayStatus
   relayLink?: string
+  relayCap: RelayCapabilities
 }
 
 export type GroupRootKey = GroupRootKey.Private | GroupRootKey.Public
@@ -3356,6 +3357,13 @@ export namespace ProxyError {
   }
 }
 
+export interface PublicGroupAccess {
+  groupWebPage?: string
+  groupDomain?: string
+  domainWebPage: boolean
+  allowEmbedding: boolean
+}
+
 export interface PublicGroupData {
   publicMemberCount: number // int64
 }
@@ -3364,6 +3372,7 @@ export interface PublicGroupProfile {
   groupType: GroupType
   groupLink: string
   publicGroupId: string
+  publicGroupAccess?: PublicGroupAccess
 }
 
 export type RCErrorType = 
@@ -3752,6 +3761,10 @@ export namespace RcvMsgError {
   }
 }
 
+export interface RelayCapabilities {
+  baseWebUrl?: string
+}
+
 export interface RelayProfile {
   displayName: string
   fullName: string