fix(tron-wallet-snap): stop wrapping submitRequest response in v1 KeyringResponse envelope

[hmalik88]

Explanation

• submitRequest in handlers/keyring/keyring.ts was returning { pending: false, result: Json }, the v1 KeyringResponse envelope, instead of raw Json
• Keyring API v2's SnapKeyring.submitRequest() calls the snap directly and expects unwrapped Json back; passing the envelope through meant callers received the wrapper object instead of the actual signing result
• Changed return type from Promise<KeyringResponse> → Promise<Json>, removed the KeyringResponse import, updated 2 test assertions accordingly

Test plan

• yarn workspace @metamask/tron-wallet-snap run test
• Verify Tron Sign Message e2e in the extension passes once a preview build from this branch is bumped in the extension PR

References

N/A

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

[hmalik88]

@metamaskbot publish-preview

[github-actions]

Preview builds have been published. Learn how to use preview builds in other projects.

Expand for full list of packages and versions.

@metamask-previews/bitcoin-wallet-snap@2.0.0-preview-e3b05f64
@metamask-previews/snap-networks-utils@0.0.0-preview-e3b05f64
@metamask-previews/tron-wallet-snap@2.0.0-preview-e3b05f64

[stanleyyconsensys]

LGTM