HSM consolidation, part 2: restart sUSDS/sUSDe conversion

Background

Referendum [#367] delisted sUSDS and sUSDe from the Hollar Stability Module. The delisting itself completed successfully — both assets are removed and the HSM now accepts only aUSDT and aUSDC — but the conversion DCAs terminated early due to a bug in the DCA pallet: when the absolute minAmountOut floor becomes the binding trade limit, a failed trade surfaces a non-retryable router error and the schedule terminates permanently instead of retrying. A runtime fix is in progress.

As a result, the scheduled day-5 cleanup swept the still-unconverted sUSDS/sUSDe out of the HSM into the Treasury.

This referendum completes the original plan from the Treasury side.

What it does

At enactment — restart the conversions (from the Treasury):

1. DCA sUSDe → aUSDT: ~$500 per trade (400 sUSDe), one trade every 10 minutes, ~2.8 days total
2. DCA sUSDS → aUSDC: ~$500 per trade (450 sUSDS), one trade every 10 minutes, ~1.5 days total

Both schedules are open-ended and self-terminate when the balances are exhausted. Parameters are adjusted from the first attempt: absolute floors sit at 95% of the current peg (wide of the ~1% spread where arbitrageurs demonstrably defend the price, so they act only as a depeg stop) while the 1% max-slippage-vs-oracle guard continues to protect each individual trade.

Day 5 (scheduled on-chain by this referendum):

3. Transfer exactly 101,244.405279 aUSDT + 101,000 aUSDC from the Treasury to the HSM
4. Swap a fixed 90,000 aUSDT → HOLLAR through the HSM (1:1 mint, no price impact) — realizing the remaining protocol profit to the Treasury in HOLLAR. A fixed amount is used instead of a sweep so the step converts exactly what is intended regardless of any upstream surprises.

The Treasury retains the remainder (~5–6k aUSDT, ~3k aUSDC plus sub-trade dust) as margin.

Resulting state

• HSM: aUSDT/aUSDC-only collateral, exactly 100% backed (plus the 90k aUSDT backing the step-4 mint 1:1, and it only accrues further via aToken interest).
• Treasury: ~90k HOLLAR of additional realized HSM profit (on top of ~30k realized by the first referendum), plus a small stablecoin buffer.
• Combined with part 1, total realized HSM profit lands at ~$120k as originally proposed.

Execution safety

• Full preimage dry-run on a chopsticks fork of mainnet: all calls execute successfully.
• The aToken transfer path and the fixed HSM swap were additionally executed against forked live state.
• The day-5 step runs as a force_batch: no single failing item can block the others, and the fixed swap size caps the amount that can move in any scenario.