admin: add sentinel commands for validator multicast publisher management

Add sentinel subcommand to doublezero-admin with two commands:
- find-validator-multicast-publishers: cross-reference onchain IBRL
  users with validator metadata to show publisher status
- create-validator-multicast-publishers: bulk-create multicast
  publisher users for IBRL validators via 3-step onchain flow

Shared library crate (doublezero-sentinel) provides readers, writers,
and pure logic with unit tests. DZClient gets rpc_client() and
payer_keypair() accessors for sentinel command integration.

Author: snormore

CHANGELOG.md

@@ -10,7 +10,7 @@ All notable changes to this project will be documented in this file.
 
 - CLI
   - Reset SIGPIPE to SIG_DFL at the start of main() in all 3 CLI binaries (doublezero, doublezero-geolocation, doublezero-admin) so the process exits silently like standard CLI tools
-- SDK
+  - Add sentinel admin commands to find and create multicast publishers for IBRL validators
   - Add Go SDK for shred subscription program with read-only account deserialization (epoch state, seat assignments, pricing, settlement, validator client rewards), PDA derivation helpers, RPC fetchers, compatibility tests, and a fetch example CLI
 - Tools
   - Add `twamp-debug` diagnostic tool for testing kernel timestamping support on switches; sends real TWAMP probes to verify which SO_TIMESTAMPING modes (RX/TX software/hardware/sched) actually deliver timestamps, and reports RTT statistics comparing userspace vs kernel timestamp sources

Cargo.lock

@@ -13,6 +13,7 @@ members = [
     "smartcontract/programs/doublezero-geolocation",
     "smartcontract/programs/common",
     "e2e/docker/ledger/fork-accounts",
+    "crates/sentinel",
 ]
 default-members = []
 exclude = [
@@ -69,6 +70,7 @@ log = "0"
 metrics = "0"
 metrics-util = "0"
 mockall = "0"
+reqwest = "0"
 regex = "1"
 serde = "1"
 serde_bytes = "0"
@@ -98,6 +100,7 @@ tokio = { version = "1", default-features = false, features = [
     "signal",
 ] }
 doublezero-config = { path = "config" }
+doublezero-sentinel = { path = "crates/sentinel" }
 doublezero_cli = { path = "smartcontract/cli" }
 doublezero-program-common = { path = "smartcontract/programs/common" }
 doublezero_sdk = { path = "smartcontract/sdk/rs" }

Cargo.toml

@@ -44,3 +44,4 @@ doublezero_cli.workspace = true
 doublezero-config.workspace = true
 doublezero-serviceability.workspace = true
 doublezero-program-common.workspace = true
+doublezero-sentinel.workspace = true

controlplane/doublezero-admin/Cargo.toml

@@ -1,4 +1,4 @@
-use super::multicast::MulticastCliCommand;
+use super::{multicast::MulticastCliCommand, sentinel::SentinelCliCommand};
 use crate::cli::{
     accesspass::AccessPassCliCommand, config::ConfigCliCommand, contributor::ContributorCliCommand,
     device::DeviceCliCommand, exchange::ExchangeCliCommand, globalconfig::GlobalConfigCliCommand,
@@ -66,6 +66,9 @@ pub enum Command {
     /// Manage multicast
     #[command()]
     Multicast(MulticastCliCommand),
+    /// Sentinel admin commands
+    #[command()]
+    Sentinel(SentinelCliCommand),
     /// Export all data to files
     #[command()]
     Export(ExportCliCommand),

controlplane/doublezero-admin/src/cli/command.rs

@@ -10,5 +10,6 @@ pub mod location;
 pub mod multicast;
 pub mod multicastgroup;
 pub mod permission;
+pub mod sentinel;
 pub mod tenant;
 pub mod user;