Bera_Module fails to stake in BGTStaker due to missing Boost integration

D2's Berachain integration includes Bera_Module::bera_bgt_stake and Bera_Module::bera_bgt_withdraw, which attempt to call BGTStaker::stake and BGTStaker::withdraw directly. Both target functions are restricted by the onlyBGT modifier, which only allows the BGT token contract itself to call them:

/// @dev Throws if called by any account other than BGT contract.
modifier onlyBGT() {
    if (msg.sender != address(stakeToken)) NotBGT.selector.revertWith();
    _;
}

function stake(address account, uint256 amount) external onlyBGT {
    _stake(account, amount);
}

To actually stake in BGTStaker, a user must go through the BGT token's boost flow:

1. Call BGT::queueBoost and BGT::activateBoost to boost a validator.
2. Call BGT::queueDropBoost and BGT::dropBoost to exit the boost.

The strategy never calls these functions. Therefore every call to bera_bgt_stake or bera_bgt_withdraw hits the onlyBGT check and reverts.

• The protocol cannot earn $BGT rewards from BGTStaker as intended.
• To access these rewards the strategy must integrate with the boost functionality of the BGT token rather than calling BGTStaker directly.
• Missed staking incentives reduce the protocol's overall earnings on Berachain.

Re-implement the BGT staking path using the boost flow on the BGT token: queue and activate a boost on the targeted validator, then later queue and drop the boost to exit. Update the module's external surface and integration tests to validate against the public Berachain reference implementations.

D2: Fixed in 11c9407.

Cyfrin: Verified.