Optimize Gas Efficiency of Contracts

[brolag]

Description: Optimize the gas efficiency of the vault and controller contracts to ensure the system is economical to use.

Subtasks:

• Review and optimize state variable usage.
• Consider batch processing of collateral deposits or withdrawals.
• Evaluate gas-heavy operations and look for optimizations (e.g., using immutable where appropriate).
• Write tests to compare gas usage before and after optimization.

Acceptance Criteria:

• Gas optimizations are applied without affecting core functionality.
• Gas usage is reduced by a measurable percentage.
• Tests confirming functionality and gas savings pass.