Feature Request: Add optional timeout parameter to switchChain

[Zelys-DFKH]

Problem

switchChain can hang indefinitely on mobile wallets over WalletConnect when:

• The wallet app is backgrounded
• The user ignores the chain switch prompt
• The request is dropped mid-flight

The promise never rejects, leaving users stuck with no error feedback.

In production, we work around this with Promise.race() + manual 30-second timeouts, but this forces every consumer to re-implement the same fragile workaround.

Proposed Solution

Add an optional timeout parameter (milliseconds) to switchChain. If the request doesn't resolve within that window, the promise rejects with a clear SwitchChainTimeoutError.

const { switchChainAsync } = useSwitchChain();

try {
  await switchChainAsync({ 
    chainId: 137, 
    timeout: 30_000  // 30 second timeout
  });
} catch (error) {
  if (error.name === 'SwitchChainTimeoutError') {
    // Handle timeout — wallet backgrounded or request dropped
  }
}

Implementation Notes

Following waitForTransactionReceipt precedent:

• Optional per-call parameter in SwitchChainParameters
• setTimeout() + Promise.race() for timeout implementation
• New SwitchChainTimeoutError extending BaseError
• No default timeout (let consumers decide)

Use Case

DeFi apps need reliable chain switching before transaction submission. A timeout parameter eliminates the need for workarounds and gives developers control over their UX when wallets become unresponsive.