Implement CIP-0149 on GovTool

### 💡 Suggestion or feature

Implement the opt-in standard for DRep compensation as described in [CIP-0149](https://github.com/cardano-foundation/CIPs/tree/master/CIP-0149) on GovTool. The standard allows users to donate a percentage of their staking rewards to their DRep when delegating.

### Who does this help?

1. **Ada holders**: They will have the option to donate a percentage of their staking rewards to their chosen DRep (Delegation Representative), promoting a more interactive and rewarding experience within the Cardano ecosystem.
2. **DReps**: They will receive compensation in the form of a percentage of staking rewards from their delegators, incentivizing them to continue providing valuable services to the community.
3. **The broader Cardano community**: This feature will facilitate experimentation and data collection on DRep compensation, helping to inform future decisions on the topic and potentially leading to a more robust and effective governance system.

### How might we do this?

Modify the Gov-Tools UI and backend to support the new standard. This includes adding a prompt for users to opt-in to donate a percentage of their staking rewards to their DRep and storing the percentage in the transaction metadata.

Use [the grant.](https://docs.intersectmbo.org/cardano-facilitation-services/cardano-budget/intersect-administration-services/2025-apply-for-tender/open-tenders/civics-committee/cip-149-optional-drep-compensation)

### Anything else you might want to add?

CIP-0149 Optional DRep Compensation Grant Application criteria are to be published soon!