feat: add sell-if-deficit command to Scrypt adapter

[TaprootFreak]

Summary

• Adds sell-if-deficit command to ScryptAdapter that conditionally sells EUR for BTC when Bitcoin on-chain (asset 113) has a balance below its rule's minimum
• If no BTC deficit exists, falls through via onFail to the existing sell EUR → USDT action (233)
• Only sells enough EUR to cover the BTC deficit (up to optimal), remaining EUR surplus is handled in the next cycle via USDT

DB setup required after merge

-- 1. Create new action
INSERT INTO liquidity_management_action (system, command, tag, params, onSuccessId, onFailId)
VALUES ('Scrypt', 'sell-if-deficit', 'SCRYPT EUR→BTC if deficit',
        '{"tradeAsset":"BTC","checkAssetId":113}', NULL, 233);

-- 2. Update rule 313 to use new action as redundancy start
UPDATE liquidity_management_rule
SET redundancyStartActionId = (
  SELECT id FROM liquidity_management_action
  WHERE command = 'sell-if-deficit' AND system = 'Scrypt'
)
WHERE id = 313;

Flow

EUR > 1'000 (Rule 313)
  → sell-if-deficit: check Bitcoin/BTC balance < minimal?
    → YES: sell EUR for BTC (amount = deficit to optimal)
    → NO:  onFail → Action 233 (sell EUR → USDT, as before)

Test plan

• Verify build passes
• Deploy to staging and create DB actions
• Test with BTC deficit: EUR should be sold for BTC
• Test without BTC deficit: EUR should fall through to USDT sell
• Verify amount is capped to BTC deficit (not full EUR surplus)