POST Initiate Privacy Deposit

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OVERVIEW
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Endpoint: POST /api/v1/deposit/initiate
Method: POST
Authentication: Optional
Rate Limit: 30 requests/minute

PURPOSE:
Initiates a privacy deposit by registering commitment data and returning
transaction parameters for on-chain submission.

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REQUEST BODY
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{
  "poolId": "cipherx-bsc-01",
  "denomination": "0.1",
  "commitment": "0x7c5b3a1d9e8f0c2b...",
  "fromAddress": "0xabc123def456...",
  "clientId": "web-dapp-v1.0"
}

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RESPONSE
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{
  "success": true,
  "depositId": "dep_cx_1234567890abcdef",
  "transactionData": {
    "to": "0xE4f77e1E0d6dE17c310FdFA2c088D40222Ab787b",
    "data": "0x...",
    "value": "100000000000000000",
    "gasLimit": "500000"
  },
  "expectedLeafIndex": 847
}