Re-implement proof of membership for the profile showcase communities

[MishkaRogachev]

Description

Building the profile showcase for a contact gets stuck on FetchCommunity call:

---------------------------------------> BuildProfileShowcaseFromIdentity
---------------------------------------> 1
---------------------------------------> fetching community: 0x0297e69bd1fa8f19c2a484d25ed17860fa41cadacb454dbee96118491f0b0b99fe

Probably the problem because of missing shard:

       community, err := m.FetchCommunity(&FetchCommunityRequest{
            CommunityKey:    message.CommunityId,
            Shard:           nil,
            TryDatabase:     true,
            WaitForResponse: true,
        })

Temporary this code is removed

New solution should request communities on the receiver's side

[MishkaRogachev]

initial code:

		community, err := m.FetchCommunity(&FetchCommunityRequest{
			CommunityKey:    message.CommunityId,
			Shard:           nil,
			TryDatabase:     true,
			WaitForResponse: true,
		})
		if err != nil {
			m.logger.Warn("failed to fetch community for profile entry ", zap.Error(err))
		}

		if community != nil && community.Encrypted() {
			grant, err := community.VerifyGrantSignature(message.Grant)
			if err != nil {
				m.logger.Warn("failed to verify grant signature ", zap.Error(err))
				entry.MembershipStatus = identity.ProfileShowcaseMembershipStatusNotAMember
			} else {
				if grant != nil && bytes.Equal(grant.MemberId, crypto.CompressPubkey(senderPubKey)) {
					entry.MembershipStatus = identity.ProfileShowcaseMembershipStatusProvenMember
				} else { // Show as not a member if membership can't be proven
					entry.MembershipStatus = identity.ProfileShowcaseMembershipStatusNotAMember
				}
			}
		} else if community != nil {
			// Use member list as a proof for unecrypted communities
			if community.HasMember(senderPubKey) {
				entry.MembershipStatus = identity.ProfileShowcaseMembershipStatusProvenMember
			} else {
				entry.MembershipStatus = identity.ProfileShowcaseMembershipStatusNotAMember
			}
		}

[MishkaRogachev]

There is a problem in the current backend implementation:
When status-go receives a contact code message from a contact, a profile showcase for that contact is collected and sent with a signal to the client. Since there is a rule that you can't send requests to the network on network events (e.g. to request community), I plan to remove the collection of the profile showcase by signal and request the data explicitly from the ui

[MishkaRogachev]

status-im/status-go#4982