feat: wire SQLite replication between site nodes and fix ConfigurationDatabase tests

Add SiteReplicationActor (runs on every site node) to replicate deployed
configs and store-and-forward buffer operations to the standby peer via
cluster member discovery and fire-and-forget Tell. Wire ReplicationService
handler and pass replication actor to DeploymentManagerActor singleton.

Fix 5 pre-existing ConfigurationDatabase test failures: RowVersion NOT NULL
on SQLite, stale migration name assertion, and seed data count mismatch.

tests/ScadaLink.ConfigurationDatabase.Tests/SqliteTestHelper.cs

@@ -1,13 +1,15 @@
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Diagnostics;
 using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using ScadaLink.Commons.Entities.Deployment;
 using ScadaLink.ConfigurationDatabase;
 
 namespace ScadaLink.ConfigurationDatabase.Tests;
 
 /// <summary>
-/// Test DbContext that maps DateTimeOffset to a sortable string format for SQLite.
-/// EF Core 10 SQLite provider does not support ORDER BY on DateTimeOffset columns.
+/// Test DbContext that adapts SQL Server-specific features for SQLite:
+/// - Maps DateTimeOffset to sortable ISO 8601 strings (SQLite has no native DateTimeOffset ORDER BY)
+/// - Replaces SQL Server RowVersion with a nullable byte[] column (SQLite can't auto-generate rowversion)
 /// </summary>
 public class SqliteTestDbContext : ScadaLinkDbContext
 {
@@ -19,6 +21,16 @@ public class SqliteTestDbContext : ScadaLinkDbContext
     {
         base.OnModelCreating(modelBuilder);
 
+        // SQLite cannot auto-generate SQL Server rowversion values.
+        // Replace with a nullable byte[] column so inserts don't fail with NOT NULL constraint.
+        modelBuilder.Entity<DeploymentRecord>(builder =>
+        {
+            builder.Property(d => d.RowVersion)
+                .IsRequired(false)
+                .IsConcurrencyToken(false)
+                .ValueGeneratedNever();
+        });
+
         // Convert DateTimeOffset to ISO 8601 string for SQLite so ORDER BY works
         var converter = new ValueConverter<DateTimeOffset, string>(
             v => v.UtcDateTime.ToString("o"),