feat: support keystone usb keyring

[Qkin-Keystone]

Explanation

Adds Keystone hardware keyring type and integrates display names across account tree and accounts controllers. This new keyring will be able to handle USB as a transport layer for the keystone hardware wallet.

References

MetaMask/metamask-extension#33980

Changelog

Add keystone usb keyring

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

Introduces KeyringTypes.keystone and wires up user-facing names across controllers.

• Add keystone to KeyringTypes enum in KeyringController.ts
• Map Keystone wallet and Keystone Account group prefix in account-tree-controller rule (rules/keyring.ts)
• Update accounts-controller keyringTypeToName to return Keystone

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