Added a preliminary guide page to instruct how to use the service.

New users are directed to the guide page automatically.

The guide is always accessible from the menu.

Reputation now matches rating scale visually. (1 thumb = 1 reputation block)

Follow settings are now more discoverable.

The text focuses now first on feed creation, which is available for free and immediately regardless of network effects. Next: onboarding and UI should emphasize personal feed building.