Improvements to onboarding process

[sneakers-the-rat]

From thread in discord - https://discord.com/channels/1049136631065628772/1305157868881711166

• customize welcome email with nms specific things, how to get to the wiki, how to get to the discord, whatever else we want
• decrease delay for initial email sent after an account to 0 - welcome your account was approved!
• maybe add second email with a ~day's delay if they haven't signed in again
• make the local feed the default thing you see when you go to root domain when you are following less than n people
• make the /start page the default until it is explicitly dismissed