Clean up %spaces & %passports

[drunkplato]

• [x] Merge %spaces and %passports agents
• [x] Refactor invite flow
• [x] Restructure subscriptions
• [ ] Groups 2

[drunkplato]

There was an issue with someone being kicked and rejoining and the discovery taking significant time. Errors in subscriptions

[drunkplato]

agent design template

app/spaces.hoon

There are two concepts here: actions and reactions.

• actions are pokes.
  • the action arm handles state updates
• reactions handle updates from subscriptions.
  • the reaction arm handles subscriptions updates from a remote host

++  core  .
::
++  spaces
  ++  action
    ++  handle-add
    ++  handle-update
    ++  handle-remove
    ++  handle-kicked
    ++  handle-joined
  ++  reaction
    ++  on-initial
    ++  on-add
    ++  on-remove
    ++  on-joined
::
++  visa
  ++  action
    ++  handle-send
    ++  handle-invited
    ++  handle-accept
    ++  handle-decline
    ++  handle-stamped
    ++  handle-kicked
  ++  reaction
    ++  on-sent
    ++  on-accepted
    ++  on-kicked
::