feat: abstract away wallet type specification with auto-detection

[mustafa-poly]

Summary

Adds wallet type auto-detection so users no longer need to manually specify whether their wallet is a Polymarket Proxy or Gnosis Safe. Previously, creating a client with a smart-contract wallet required knowing and passing both signatureType and funderAddress:

// Before: must know the exact wallet type
const client = new ClobClient(
    host, chainId, wallet, creds,
    SignatureType.POLY_GNOSIS_SAFE,  // how do I know this?
    safeAddress,
);

Now users can use the new ClobClient.create() factory method which auto-detects the wallet type from an on-chain check:

// After: just provide funderAddress + RPC, SDK figures out the type
const client = await ClobClient.create({
    host,
    chainId,
    signer: wallet,
    creds,
    funderAddress: "0xMyPolymarketWallet...",
    rpcUrl: "https://polygon-rpc.com",
});

How It Works

The detection works by calling the Gnosis Safe getOwners() function selector (0xa0e67e2b) on the funder address:

• If the call returns data → it's a Gnosis Safe (POLY_GNOSIS_SAFE)
• If the call reverts or returns empty → it's a Polymarket Proxy (POLY_PROXY)
• If no code exists at the address → error with helpful message
• If no funderAddress or it matches the signer → EOA (no RPC call needed)

This approach is robust against factory init code hash changes (which have caused issues with CREATE2 derivation in the Rust SDK).

Changes

New: src/wallet-detection.ts

• detectWalletType(funderAddress, clientOrUrl, chainId?) — low-level detection
• resolveWalletConfig(signerAddress, options) — high-level resolver handling all cases
• WalletDetectionResult type

Modified: src/client.ts

• ClobClientConfig interface — typed config object (cleaner than 13 positional params)
• ClobClient.create(config) — async factory method with auto-detection
• Fully backward compatible: existing constructor is unchanged

Modified: src/index.ts

• Exports detectWalletType, resolveWalletConfig, WalletDetectionResult, ClobClientConfig

Updated: examples/signatureTypes.ts

• Shows both the existing explicit API and the new auto-detection flow

New Tests

• tests/wallet-detection/wallet-detection.test.ts — 14 tests for detection logic
• tests/client/create-factory.test.ts — 4 tests for factory method
• All tests use mocked PublicClient (no real RPC calls)

Backward Compatibility

This is a purely additive change. The existing ClobClient constructor, SignatureType enum, and all current APIs remain unchanged. Users can adopt ClobClient.create() at their own pace.