feat(transaction-pay-controller): enable relay validation per transaction type

[matthewwalsh0]

Explanation

The payStrategies.relay.validationEnabled flag (in the confirmations_pay_extended remote feature flag) was a plain boolean, so Relay quote validation could only be toggled globally — there was no way to enable or disable it per transaction type.

This PR replaces the boolean with an object-only schema:

validationEnabled: {
  default?: boolean;                                             // base toggle for all types (omitted = false)
  transactionTypes?: Partial<Record<TransactionType, boolean>>;  // per-type overrides
}

• default is the base toggle applied to every transaction type. When omitted, validation is off.
• A matching transactionTypes[txType] entry overrides default for that specific type (using ??, so an explicit false override correctly beats a true default).

Because the confirmations_pay_extended flag is versioned, the boolean form is dropped rather than kept for backwards compatibility — this is a breaking change to the flag shape (true is now expressed as { default: true }).

The resolver isRelayValidationEnabled gains an optional transactionType parameter, and the single call site in relay-validation.ts passes request.transaction.type. A new RelayValidationEnabledConfig type describes the flag shape.

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

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