[lending] collateral genesis export, ragnarok, and invariant

• add lending total collateral to genesis
• store migration to restore total collateral that was lost during fork
• clear total collateral and burn derived asset coins from the lending module during ragnarok
• lending invariant to ensure total collateral matches both the sum of collateral of all loans and the module balance of the associated derived asset

Closes #1490 (closed) and #2056 (closed) and #2058 (closed)