feat(sentinel): auto-manage multicast publishers

[bgm-malbeclabs]

Summary

Auto-joins validators to configured multicast publisher groups on onboarding. At startup, resolves configured group codes to onchain PDAs; on each new access pass, idempotently adds the validator to every configured multicast group's
publisher allowlist.

Changes

• Multicast publisher allowlisting on validator onboarding: after issuing an access pass, the polling sentinel iterates configured multicast group PDAs and calls add_multicast_publisher_allowlist for each. Skips groups the validator is already in (idempotency via get_access_pass pre-check). Failures are logged and metered but don't block onboarding.
• Startup group code resolution ΓÇö new resolve_multicast_group_codes fetches all MulticastGroup accounts from the DZ Ledger and maps configured codes to PDAs. Rejects duplicate codes (regardless of status) and only resolves Activated groups.
• get_access_pass and add_multicast_publisher_allowlist on DzRpcClientType: new trait methods + implementations on DzRpcClient, enabling mock-based testing.
• Configurable group codes: new multicast_group_codes setting (comma-separated, env: SENTINEL__MULTICAST_GROUP_CODES). When empty (default), allowlisting is disabled.
• Timeout on add_multicast_publisher_allowlist: wraps send_and_confirm_transaction in tokio::time::timeout(60s), matching existing billing RPC pattern.

Testing

• Add tests for multicast group code resolution (duplicates, status filtering, not-found, happy path) and 5 tests for settings parsing.

[Copilot]

Pull request overview

This pull request adds multicast publisher allowlisting functionality to the sentinel service. When validators are onboarded and granted access passes, they are automatically added to configured multicast publisher groups.

Changes:

• Added multicast_group_codes configuration setting for specifying which multicast groups to auto-join validators to
• Implemented multicast group code resolution at startup to convert codes to on-chain PDAs
• Integrated allowlist addition into the validator onboarding flow with proper error handling and metrics

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
crates/sentinel/src/settings.rs	Added multicast_group_codes setting with parsing logic to support comma-separated group codes
crates/sentinel/src/main.rs	Added startup logic to resolve multicast group codes to PDAs and pass them to PollingSentinel
crates/sentinel/src/sentinel/poller.rs	Added multicast_group_pdas field and integrated allowlist addition into validator onboarding loop with metrics
crates/sentinel/src/client/doublezero_ledger.rs	Implemented add_multicast_publisher_allowlist and resolve_multicast_group_codes methods with trait support
crates/sentinel/CHANGELOG.md	Added changelog entry for the new feature

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