feat(cluster): preserve independent replication identity

[yordis]

• Gives cluster members an independent replication identity without removing the existing TCP contract before its retirement layer.

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📥 Commits

Reviewing files that changed from the base of the PR and between 35e6eb4 and b0c8214.

⛔ Files ignored due to path filters (1)

• proto.lock is excluded by !**/*.lock

📒 Files selected for processing (10)

• src/EventStore.Core.Tests/Cluster/MemberInfoTests.cs
• src/EventStore.Core.Tests/Services/GossipService/NodeGossipServiceTests.cs
• src/EventStore.Core.XUnit.Tests/Configuration/ClusterNodeOptionsTests/when_building/with_cluster_node_and_custom_settings.cs
• src/EventStore.Core/Cluster/ClientClusterInfo.cs
• src/EventStore.Core/Cluster/ClusterInfo.cs
• src/EventStore.Core/Cluster/MemberInfo.cs
• src/EventStore.Core/ClusterVNode.cs
• src/EventStore.Core/Data/GossipAdvertiseInfo.cs
• src/EventStore.Core/Data/VNodeInfo.cs
• src/EventStore.Core/Services/Gossip/NodeGossipService.cs

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Walkthrough

The change adds replication endpoints to cluster data models, node construction, gossip metadata, gRPC conversion, and client cluster information. Missing replication endpoints fall back to HTTP endpoints. Tests cover round trips, advertisement, gossip, and fallback behavior.

Changes

Replication endpoint support

Layer / File(s)	Summary
Endpoint data models src/EventStore.Core/Cluster/MemberInfo.cs, src/EventStore.Core/Data/VNodeInfo.cs, src/EventStore.Core/Data/GossipAdvertiseInfo.cs	MemberInfo, VNodeInfo, and GossipAdvertiseInfo now store replication endpoints. Endpoint matching, equality, hashing, updates, and string output include the replication endpoint. Missing values fall back to the HTTP endpoint.
Replication endpoint construction and gossip wiring src/EventStore.Core/ClusterVNode.cs, src/EventStore.Core/Services/Gossip/NodeGossipService.cs	ClusterVNode constructs and advertises replication endpoints from interface settings. Initial gossip metadata includes the replication endpoint.
gRPC and client endpoint propagation src/Protos/Grpc/cluster.proto, src/EventStore.Core/Cluster/ClusterInfo.cs, src/EventStore.Core/Cluster/ClientClusterInfo.cs	The gRPC MemberInfo message carries replication endpoints. Cluster conversion preserves them, and ClientMemberInfo exposes the replication host and port.
Replication endpoint validation src/EventStore.Core.Tests/Cluster/MemberInfoTests.cs, src/EventStore.Core.Tests/Services/GossipService/NodeGossipServiceTests.cs, src/EventStore.Core.XUnit.Tests/Configuration/ClusterNodeOptionsTests/when_building/with_cluster_node_and_custom_settings.cs	Tests cover explicit endpoints, HTTP fallback, gRPC round trips, client mapping, gossip preservation, and configured advertisement ports.

Priority: ➖ Normal

Estimated code review effort: 3 (Moderate) | ~25 minutes

Change: Feature

Sequence Diagram(s)

sequenceDiagram
  participant ClusterVNode
  participant GossipAdvertiseInfo
  participant MemberInfo
  participant ClusterInfo
  ClusterVNode->>GossipAdvertiseInfo: create advertised replication endpoint
  ClusterVNode->>MemberInfo: include endpoint in initial gossip metadata
  MemberInfo->>ClusterInfo: serialize replication endpoint
  ClusterInfo->>MemberInfo: restore replication endpoint

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🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 47 functions across 12 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: preserving an independent replication identity for cluster members.
Description check	✅ Passed	The description directly explains that cluster members gain an independent replication identity while the existing TCP contract remains available.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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_{A rabbit hops where endpoints meet
Replication travels on steady feet
Gossip carries the port along
gRPC keeps the path strong
HTTP waits when values are gone}

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[cursor]

PR Summary

Medium Risk
Adds a new gossip proto field and changes how cluster nodes identify and advertise replication endpoints, which affects cluster coordination but keeps backward compatibility via HTTP fallbacks.

Overview
Cluster members now carry a dedicated replication endpoint alongside existing TCP/HTTP addresses, so replication can be advertised and matched independently while the legacy internal-TCP contract remains unchanged.

The change threads ReplicationEndPoint through VNodeInfo, GossipAdvertiseInfo, and MemberInfo (defaulting to the HTTP endpoint when unset), maps it in gRPC gossip (replication_end_point on MemberInfo), and builds it at node startup from ReplicationIp/ReplicationPort with optional ReplicationPortAdvertiseAs. Gossip updates, client cluster info, and Is() endpoint matching now treat replication as its own identity; tests cover gRPC round-trip, HTTP fallback for missing values, gossip seed handling, and advertise-port configuration.

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Actionable comments posted: 1

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Inline comments:
In `@src/EventStore.Core/ClusterVNode.cs`:
- Around line 319-321: Update the endpoint construction around
replicationPortAdvertiseAs to create the replication endpoint using the resolved
replication host and advertised replication port, then pass it to the VNodeInfo,
GossipAdvertiseInfo, and MemberInfo.Initial construction calls so each publishes
the configured replication endpoint instead of falling back to the HTTP
endpoint.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Advanced

Run ID: bceb3cb4-f941-40aa-9477-9f589eed9cd0

📥 Commits

Reviewing files that changed from the base of the PR and between 2931754 and 35e6eb4.

⛔ Files ignored due to path filters (1)

• proto.lock is excluded by !**/*.lock

📒 Files selected for processing (11)

• src/EventStore.Core.Tests/Cluster/MemberInfoTests.cs
• src/EventStore.Core.XUnit.Tests/Configuration/ClusterNodeOptionsTests/when_building/with_cluster_node_and_custom_settings.cs
• src/EventStore.Core.XUnit.Tests/Configuration/ClusterVNodeOptionsTests.cs
• src/EventStore.Core/Cluster/ClientClusterInfo.cs
• src/EventStore.Core/Cluster/ClusterInfo.cs
• src/EventStore.Core/Cluster/MemberInfo.cs
• src/EventStore.Core/ClusterVNode.cs
• src/EventStore.Core/Configuration/ClusterVNodeOptions.cs
• src/EventStore.Core/Data/GossipAdvertiseInfo.cs
• src/EventStore.Core/Data/VNodeInfo.cs
• src/Protos/Grpc/cluster.proto

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