Survival claim limits raised

Claim blocks were too tight for anyone building something ambitious. Two changes:

• The base allowance is up from 12,000 to 20,000 blocks.
• Blocks now accrue per hour played, not per day logged in. Playing three hours in one evening earns three hours' worth.

Existing players got the difference added retroactively. If your total looks wrong, open a ticket in Discord and we'll check the log.