Now that push requests are supported in index-v1, there needs to be some controls on them so that they are not easily abused.
- First, this adds a global preference that disables push requests by default. Users must enable "Expert Mode", then "Allow Push Requests" for them to work. Whitelabel builds can set that preference in their whitelabeling.
- Then this includes an audit how the server could abuse the push requests, since we aim to trust the server as little as possible.