refactor(multichain-account-service)!: replace withKeyring usage with withKeyringV2

[hmalik88]

Explanation

Changes

Base provider & types

• Add KeyringControllerWithKeyringV2Action to the messenger's AllowedActions
• Split BaseBip44AccountProvider.withKeyring into two helpers:
• withKeyring; calls KeyringController:withKeyring (V1). Used by SnapAccountProvider until its V2 migration lands.
• withKeyringV2<SelectedKeyring extends KeyringV2>; calls KeyringController:withKeyringV2. Used by the EVM provider.

EvmAccountProvider

• All call sites moved to withKeyringV2
• Callbacks use V2 keyring methods: getAccounts() returns KeyringAccount[], createAccounts({ type: 'bip44:derive-index', entropySource, groupIndex }) replaces addAccounts()
• Range creation loops with bip44:derive-index since HdKeyringV2 does not support bip44:derive-index-range
• #getAddressFromGroupIndex is now typed against HdKeyring from @metamask/eth-hd-keyring/v2 and peeks via keyring.root.deriveChild(groupIndex) (the V2 wrapper forwards the legacy root getter)
• discoverAccounts keeps the V1-style peek-then-create pattern: peek the address → check on-chain activity outside the keyring mutex → create the account only if there is activity → look up the InternalAccount from AccountsController after the withKeyringV2 callback completes
• KeyringCapabilities and Keyring types now come from @metamask/keyring-api/v2

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

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Note

Medium Risk
Moderate risk because it changes the EVM account-creation and discovery path to use the V2 keyring interface and different keyring methods; regressions could affect account derivation/indexing and discovery behavior.

Overview
BREAKING: Migrates the EVM account provider from KeyringController:withKeyring (V1) to KeyringController:withKeyringV2 (V2) and updates types/messenger wiring to allow the new action.

EvmAccountProvider now uses V2 keyring APIs (getAccounts returning KeyringAccount[], createAccounts replacing addAccounts, and deriving IDs from returned accounts) and changes range creation to loop per index (since HdKeyringV2 doesn’t support range creation). Discovery now “peeks” the derived address via the V2 HD keyring root before creating the account, and adds explicit assertions/error handling when keyring creation returns no account.

Tests were updated accordingly, including new V2 keyring mocks and deterministic derivation fixtures, and the changelog documents the breaking migration.

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