feat: add resolveAccountAddress method to KeyringHandler for dApp connectivity routing

[Battambang]

Explanation

This PR contributes to supporting the Bitcoin dApp connectivity.
It's adding the resolve account address Keyring method.

It is part from the initial PR #564 feat: enable account address resolution to support dApps connectivity to split the work into 3 smaller PRs:
#589 refactor: move validation structs and add account field
#590 feat: add resolveAccountAddress method to KeyringHandler for dApp connectivity routing
#591 feat: add confirmation dialog before sendTransfer and before signing a PSBT from the keyring handler

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

---

Note

Medium Risk
Adds a new Keyring RPC method used for dapp request routing and tightens request validation shapes (including a required account.address field), which could affect compatibility with existing callers if they don’t send the new params.

Overview
Adds Keyring API support for keyring_resolveAccountAddress by implementing KeyringHandler.resolveAccountAddress, which validates the incoming Bitcoin request, filters accounts by scope, and returns a CAIP-10 style scope:address (or null on failure) to enable MetaMask dapp signing request routing.

Updates Bitcoin request validation by centralizing the Superstruct schemas in validation.ts (and reusing them from KeyringRequestHandler), requiring an explicit params.account.address across signing/PSBT/transfer/UTXO/message requests; tests and integration fixtures are adjusted accordingly. Changelog and snap manifest shasum are updated.

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[Battambang]

@metamaskbot publish-preview

[github-actions]

Preview builds have been published. See these instructions for more information about preview builds.

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{
  "@metamask-previews/bitcoin-wallet-snap": "1.10.0-preview-4a5f56f"
}

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[Battambang]

@metamaskbot publish-preview

[github-actions]

Preview builds have been published. See these instructions for more information about preview builds.

Expand for full list of packages and versions.

{
  "@metamask-previews/bitcoin-wallet-snap": "1.10.1-preview-6e614c7"
}