AP => Bluesky: don't wait for follow before sending posts

[snarfed]

Right now, if you opt in from the fediverse, we still don't send your posts to Bluesky until someone there follows you. This consistently confuses people; we should change it to proactively send posts, especially since fediverse people are explicitly opting in.

[snarfed]

Done! Hopefully.

[qazmlp]

This won't work unless a bridged user (from any network, due to the shared inbox) follows the AP user.
Most AP servers don't send posts to remote instances unless there are any followers of that specific local user there.

Related to #975 and #1018.

[snarfed]

Hah, true, I forgot the other part of this that I planned to do: have the bot user follow them back. Reopening.

[snarfed]

Done! Now, when someone on the fediverse follows @[email protected], it will follow them back, which should make sure that we start receiving their new posts immediately.

Now, for the second part of this: backfilling and making that bot user follow all existing fediverse users.

[snarfed]

Running this script now:

bot = Web.get_by_id('bsky.brid.gy')
now = util.now().isoformat()

for user in ActivityPub.query(ActivityPub.enabled_protocols == 'atproto'):
  follow_id = f'https://bsky.brid.gy/#follow-back-{user.key.id()}-{now}'
  follow = Object(id=follow_id, source_protocol='web', our_as1={
      'objectType': 'activity',
      'verb': 'follow',
      'id': follow_id,
      'actor': bot.key.id(),
      'object': user.key.id(),
  })
  try:
    user.send(follow, user.target_for(user.obj), from_user=bot)
  except BaseException as e:
    logging.info('', exc_info=True)