feat(liquidity-management): add swap command to DfxDexAdapter

[TaprootFreak]

Summary

• Add new swap command to DfxDexAdapter for cross-asset liquidity acquisition via DEX
• Unlike purchase (same asset), swap allows converting one asset to another (e.g., USDC → EURC)
• Enables automatic EURC liquidity provisioning using USDC via Uniswap

Changes

• Add SWAP = 'swap' to DfxDexAdapterCommands enum
• Implement swap() method that:
  • Takes sourceAsset from action params (e.g., "USDC")
  • Uses targetAsset from rule (e.g., "EURC")
  • Checks available source liquidity before swap
  • Calls dexService.purchaseLiquidity() with different reference/target assets
• Add param validation for sourceAsset parameter
• Reuse checkSellPurchaseCompletion for order tracking

Usage

Action params: {"sourceAsset": "USDC"}

Example LiquidityManagementAction:

INSERT INTO liquidity_management_action (system, command, params)
VALUES ('DfxDex', 'swap', '{"sourceAsset":"USDC"}');

Example LiquidityManagementRule for EURC:

INSERT INTO liquidity_management_rule (
  status, context, targetAssetId, minimal, optimal, maximal,
  deficitStartActionId, redundancyStartActionId, delayActivation
) VALUES ('Active', 'Ethereum', 169, 1000, 5000, 20000,
  <new_action_id>, 99, 1);

Test plan

• Deploy to dev environment
• Create test action with {"sourceAsset": "USDC"}
• Create test rule for EURC with deficit action
• Verify swap executes correctly via Uniswap pool
• Check order completion tracking works

[github-actions]

🤖 PR Review Bot

⚠️ Security: 0 critical, 67 high vulnerabilities

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[davidleomay]

Use purchase/sell instead of swap (same functionality), add a trade asset parameter