feat: yield.xyz POC

.env

@@ -304,3 +304,12 @@ VITE_FEATURE_PLASMA=true
 VITE_HYPEREVM_NODE_URL=https://rpc.hyperliquid.xyz/evm
 VITE_FEATURE_HYPEREVM=true
 VITE_FEATURE_NEAR=false
+
+# Yield.xyz Feature Flag
+VITE_FEATURE_YIELD_XYZ=false
+
+# Yield.xyz API
+VITE_YIELD_XYZ_API_KEY=
+
+# Yield.xyz Multi-Account Fetching
+VITE_FEATURE_YIELD_MULTI_ACCOUNT=false

.env.development

@@ -93,3 +93,9 @@ VITE_FEATURE_NOTIFICATIONS_WEBSERVICES=true
 VITE_FEATURE_WC_DIRECT_CONNECTION=true
 VITE_FEATURE_CETUS_SWAP=true
 VITE_FEATURE_NEAR=true
+
+# Yield.xyz Feature Flag
+VITE_FEATURE_YIELD_XYZ=true
+
+# Yield.xyz API
+VITE_YIELD_XYZ_API_KEY=06903960-e442-4870-81eb-03ff3ad4c035

COSMOS_STAKING_SPIKE.md

@@ -0,0 +1,112 @@
+# Cosmos Staking via Yield XYZ - Technical Spike
+
+## Problem
+
+Yield XYZ returns Cosmos transactions as **hex-encoded protobuf** (e.g., `0ab7010a9d010a232f636f736d6f732e7374616b696e672e763162657461312e4d736744656c656761746512760a2d...`), but our `@shapeshiftoss/hdwallet-core` expects **Amino JSON format** for signing.
+
+### Current Error
+```
+ChainAdapterError: Cannot read properties of undefined (reading 'msg')
+```
+
+The adapter's `signAndBroadcastTransaction` expects `txToSign.tx.msg[]` in Amino format, not raw protobuf bytes.
+
+## Yield XYZ Response Example
+
+```json
+{
+  "id": "f5aef598-0987-4a60-9341-9d0be2613e39",
+  "intent": "enter",
+  "type": "STAKE",
+  "yieldId": "cosmos-atom-native-staking",
+  "transactions": [
+    {
+      "id": "68a1648a-7c8c-43f9-9df5-110960148368",
+      "title": "STAKE Transaction",
+      "unsignedTransaction": "0ab7010a9d010a232f636f736d6f732e7374616b696e672e763162657461312e4d736744656c656761746512760a2d636f736d6f733161386c33737271796b356b72767a686b743763797a79353279786367687436333232773271791234636f736d6f7376616c6f70657231686a63743671376e707373707367336467767a6b33736466383973706d6c7066646e366d39641a0f0a057561746f6d12063730373036341215766961205374616b654b6974204349442d3130303912680a510a460a1f2f636f736d6f732e63727970746f2e736563703235366b312e5075624b657912230a21034d61c87b52901de0969a12d285289bec15b7a7217fe2a03132b469b55f3cb1d112040a02080118e00612130a0d0a057561746f6d12043336323910ef92161a0b636f736d6f736875622d3420f6953a",
+      "gasEstimate": "{\"amount\":\"0.003629\",\"gasLimit\":\"362863\",\"token\":{...}}"
+    }
+  ]
+}
+```
+
+## HDWallet Expected Format
+
+From `@shapeshiftoss/hdwallet-core/dist/cosmos.d.ts`:
+
+```typescript
+interface CosmosSignTx {
+  addressNList: BIP32Path;
+  tx: Cosmos.StdTx;  // <- Amino format
+  chain_id: string;
+  account_number: string;
+  sequence: string;
+}
+
+interface StdTx {
+  msg: Msg[];  // <- Amino messages
+  fee: StdFee;
+  signatures: StdSignature[];
+  memo?: string;
+}
+```
+
+## Investigation Tasks
+
+1. **Check HDWallet capabilities**
+   - Review `../shapeshiftHdWallet` repository
+   - Does hdwallet support `signDirect` (protobuf signing) in addition to `signAmino`?
+   - Look at `cosmosSignTx` implementation
+
+2. **Protobuf decoding option**
+   - Can we decode the hex protobuf to extract message types and values?
+   - Then reconstruct in Amino format?
+   - Libraries: `@cosmjs/proto-signing`, `cosmjs-types`
+
+3. **Alternative: Build our own transaction**
+   - Current workaround in `executeTransaction.ts` uses `adapter.buildDelegateTransaction()`
+   - This bypasses Yield XYZ's pre-built transaction entirely
+   - Need to pass `cosmosStakeArgs` with validator/amount/action
+
+4. **Yield XYZ API check**
+   - Does their API support returning Amino format instead of protobuf?
+   - Contact Yield XYZ support about transaction format options
+
+## Current Workaround
+
+File: `src/lib/yieldxyz/executeTransaction.ts`
+
+We're currently attempting to build the transaction ourselves using the adapter's native methods:
+
+```typescript
+const executeCosmosTransaction = async ({ cosmosStakeArgs, ... }) => {
+  const { txToSign } = await adapter.buildDelegateTransaction({
+    accountNumber,
+    wallet,
+    validator: cosmosStakeArgs.validator,
+    value: cosmosStakeArgs.amountCryptoBaseUnit,
+    chainSpecific: { gas, fee },
+    memo: '',
+  })
+
+  return adapter.signAndBroadcastTransaction({
+    signTxInput: { txToSign, wallet },
+    ...
+  })
+}
+```
+
+This requires passing `cosmosStakeArgs` from `YieldActionModal.tsx`.
+
+## Files to Investigate
+
+- `../shapeshiftHdWallet/packages/hdwallet-core/src/cosmos.ts`
+- `../shapeshiftHdWallet/packages/hdwallet-native/src/cosmos.ts`
+- `@shapeshiftoss/chain-adapters` cosmos adapter source
+- Yield XYZ API docs: https://docs.yield.xyz/docs/cosmos-atom-native-staking
+
+## Related Code
+
+- `src/lib/yieldxyz/executeTransaction.ts` - Transaction execution
+- `src/pages/Yields/components/YieldActionModal.tsx` - Modal that initiates transactions
+- `src/plugins/cosmos/hooks/useStakingAction/useStakingAction.tsx` - Existing cosmos staking pattern