fix(transaction-pay-controller): use Infura endpoint for live token balance queries

[matthewwalsh0]

Explanation

When querying a live on-chain token balance, the controller previously resolved the network client using findNetworkClientIdByChainId, which returns whatever endpoint is currently selected for that chain — including custom RPC endpoints. Custom RPC endpoints may not support the pending block tag used by these calls, causing the query to fail.

This change adds a preference for the chain's Infura endpoint when one is configured, falling back to the existing findNetworkClientIdByChainId behaviour if no Infura endpoint is configured or if the lookup throws.

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Medium Risk
Changes which RPC endpoint serves balance checks and on-chain amount reads before Relay submit; wrong endpoint selection could block or mis-validate pay deposits, though Infura preference falls back to the default client.

Overview
Introduces shared provider utilities (getNetworkClientId, rpcRequest) so chain RPC calls go through the controller messenger’s provider.request instead of ethers Web3Provider / Contract.

Live token balances (getLiveTokenBalance) now call eth_getBalance / eth_call with the pending block tag and pass preferInfura: true, picking the chain’s Infura networkClientId when configured and otherwise using findNetworkClientIdByChainId—addressing failures on custom RPCs that don’t support pending queries.

The same RPC helper path is used for fiat source amount resolution and transfer amount from tx hash (receipt logs, debug_traceTransaction, eth_getTransactionByHash). Across, Relay, and gas estimation call sites switch to getNetworkClientId for consistency.

Messenger AllowedActions and test mocks register NetworkController:getNetworkConfigurationByChainId. Changelog documents the Infura preference for live balance queries.

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