Allow ContractCalls in default/split subvariants

[smartchainark]

Currently, contractCalls only work in custom subvariant (see useRoutes.ts:276). This limits flexibility for integrators who want to:

1. Track on-chain transaction data
2. Use default UI/UX
3. Avoid custom mode's layout constraints

Proposed Solution: Add a config option to enable ContractCalls in all modes:

config: {
subvariant: 'default',
contractCalls: [...],
enableContractCallsForAllModes: true
}