List accounts using all endpoints and persist the endpoints for correct signing

[AntiD2ta]

This PR addresses critical issues with endpoint management and account persistence in distributed Dirk wallet setups that could occur in production distributed Dirk wallet setups where multiple endpoints serve different accounts. The changes ensure proper endpoint tracking for accounts and improve reliability when listing accounts across multiple endpoints.

Changes

Account Listing Improvements

• Problem: Account listing only queried a single endpoint, potentially missing accounts on other endpoints in distributed setups.
• Solution: Modified account listing to query all available endpoints and deduplicate results.

Endpoint Persistence for Correct Signing

• Problem: Accounts were not properly maintaining references to their originating endpoints, which could cause signing operations to fail in distributed setups.
• Solution: Modified account creation/retrieval logic to persist endpoint information with each account.
• Impact: Ensures signing operations use the correct endpoint associated with each account.

Golangci-lint Migration

Migrated to golangci-lint v2 and updated code to pass new linting requirements.