New workspaces: one daily email allowance until the first review, and a bot check on signup

More protection for the sending reputation every workspace shares.

• One allowance for direct email until review. Until our team has reviewed a new workspace's sending (usually within one business day), it can send up to 20 emails a day in total through one-to-one email, Bulk send, the transactional email API and flow notifications addressed outside your team. Replies to emails people send you, notifications to your own team and test sends don't count. Once approved, the limit is gone.
• Bulk send pauses with marketing. If a workspace's marketing sending is paused, Bulk send from a record list pauses too. Single emails still go.
• A quick security check on signup. Creating a new workspace now includes a Cloudflare check that most people never see.