feat(wallet): wire TransactionController into default initialization

[matthewwalsh0]

Explanation

Adds packages/wallet/src/initialization/instances/transaction-controller/ following the same pattern established by the approval-controller/ directory in #8953.

The directory contains:

• transaction-controller.ts — the InitializationConfiguration that wires TransactionController into the default wallet initialization, delegating messenger actions from the root and creating a typed child messenger for the controller
• types.ts — TransactionControllerInitMessenger, TransactionControllerInitMessengerActions, TransactionControllerInitMessengerEvents, and TransactionControllerInstanceOptions (a subset of TransactionControllerOptions that exposes only the genuinely platform-specific options; shared defaults are hardcoded in the config)

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