Track a user's last activity

A user will have an accessedAt timestamp that will update at most once
per day if they make some API call. This timestamp can then be used
find active users and calculate daily, weekly, and monthly active users.

To ensure consistent updates to the user the $user from the resource
is always updated to the user making the request, including requests
like Create Account, Update Team Membership Status, and Create Phone
Session (confirmation). This ensures the shutdown can update the
accessedAt timestamp if there was a $user set.

app/init.php

@@ -100,6 +100,7 @@ const APP_LIMIT_WRITE_RATE_DEFAULT = 60; // Default maximum write rate per rate
 const APP_LIMIT_WRITE_RATE_PERIOD_DEFAULT = 60; // Default maximum write rate period in seconds
 const APP_LIMIT_LIST_DEFAULT = 25; // Default maximum number of items to return in list API calls
 const APP_KEY_ACCCESS = 24 * 60 * 60; // 24 hours
+const APP_USER_ACCCESS = 24 * 60 * 60; // 24 hours
 const APP_CACHE_UPDATE = 24 * 60 * 60; // 24 hours
 const APP_CACHE_BUSTER = 506;
 const APP_VERSION_STABLE = '1.3.7';