feat: add optional details field to Transaction type

[danroc]

Description

This PR adds an optional details field to the Transaction type to support transaction origin tracking and security alert responses.

Current State

The Transaction type currently lacks fields to track:

• Where a transaction originated (MetaMask internally or a dapp)
• Security assessment results from the Security Alert API

Solution

Adds an optional details object containing:

• origin (optional string): Transaction request source (e.g., 'metamask' or dapp URL)
• securityAlertResponse (optional enum): Security Alert API response (benign, warning, malicious)

The implementation is backward compatibile.

Examples

N/A - This is an API enhancement that consumers can adopt incrementally.

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Note

Low Risk
Adds a backward-compatible optional field to a public type plus validation/tests; main risk is downstream consumers assuming the old shape or mishandling the new optional object.

Overview
Adds an optional details object to Transaction to carry extra context about a transaction, including an origin string and a securityAlertResponse value.

Introduces the SecurityAlertResponse enum and TransactionDetailsStruct, wires details into TransactionStruct using exactOptional (disallowing explicit undefined), and adds both runtime (TransactionStruct) and type-level (tsd) tests plus changelog documentation.

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[cursor]

Cursor Bugbot has reviewed your changes and found 2 potential issues.

[wzrdk3lly]

Thanks this looks good. Correct the successful responses types from security alerts are Benign | Warning | Malicious .