On a technical level, the best way to do prevent liquidity from being withdrawn via a proposal is to burn the initially generated fraxswap V2 LP tokens directly after the Agent Graduates. This way Agents can still deploy Agent held tokens via the proposal system.
I suggest considering adding the option for Agents to migrate their IQ liquidity into yield bearing AIQ liquidity upon Graduation, which will give Agents a revenue stream that can be distributed via proposals. Details here