Pull Request: Implement Treasury Fee Sharing Mechanism

[johdanike]

Closes #648
Summary
This PR adds an atomic fee-splitting mechanism to the Treasury contract. Transaction fees are now automatically distributed between Planters, Verifiers, and the Replanting Reserve based on configurable basis-point (bps) weights.

Key Changes

Atomic Fee Distribution: Added distribute_fees(env, from, amount) which performs all fee transfers in a single, atomic transaction. If any leg of the distribution fails, the entire transaction reverts to maintain treasury balance.

Governance-Adjustable Weights: Integrated weight management into the existing 2-of-3 multisig proposal flow. Weights are stored as basis points (sum = 10,000) and can be updated through the new governance proposal system.

Rounding Dust: Implemented logic to ensure that any integer-division dust is automatically absorbed by the Replanting Reserve pool.

Acceptance Criteria Checklist

[x] Configurable Weights: Governance can adjust planter, verifier, and reserve weights via multisig proposal.

[x] Atomic Processing: Fee division is processed atomically, ensuring no partial states.

Technical Notes

The contract utilizes the latest soroban-sdk 22.0.1 and registration syntax (env.register(Treasury, ())).

Governance paths remain consistent with the established withdrawal multisig design.

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[Idrhas]

Fix merge conflict and dont forget to Offramp your USDC on https://fundable.finance when you receive your rewards

[johdanike]

Conflicts resolved