Contacts status

[defnax]

Implemented GXS contact presence with getContactsStatus....

Included:

• away, busy, and online contact states
• Per-identity custom-state strings
• Contact-only exchange over authenticated GXS tunnels
• Persistent own status/custom state
• Transient remote-contact status
• CONTACT_STATUS_CHANGED identity events
• JSON API annotations

the GXS contact status is restricted per sender’s local contact list.
Current protections:

• Status is sent only when isARegularContact(contactId) returns true.
• Non-contact tunnels do not receive the new RS_CHAT_FLAG_GXS_CONTACT_STATUS packet.
• Incoming status is stored only if the authenticated sender is in the receiver’s regular contact list.
• Exchange occurs through the encrypted/authenticated GXS distant-chat tunnel.
• getContactsStatusList() returns entries only from mContacts.
• Each side decides independently: if Alice considers Bob a contact but Bob does not consider Alice one, Alice may advertise to Bob, but Bob will not advertise to Alice.