refactor: rename ScadaLink → ZB.MOM.WW.ScadaBridge (code + projects + namespaces)

Solution + 23 src projects + 26 test projects renamed; folders, csproj,
namespaces, and ScadaLinkDbContext/ScadaBridgeDbContext class updated.
ActorSystem "scadalink" → "scadabridge", Akka seed-node URLs migrated.
SQL roles/logins, LDAP domains, CLI command name, and CLI config dir
(~/.scadalink → ~/.scadabridge) also renamed.

Build green; 5 Host.Tests fail awaiting SQL login rename in next commit.
Pre-existing StaleTagMonitor timing flakes unchanged.

Rename script committed at tools/rename-to-scadabridge.sh.

src/ZB.MOM.WW.ScadaBridge.ClusterInfrastructure/ServiceCollectionExtensions.cs

@@ -0,0 +1,46 @@
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+using Microsoft.Extensions.Options;
+
+namespace ZB.MOM.WW.ScadaBridge.ClusterInfrastructure;
+
+/// <summary>
+/// DI registration for the Cluster Infrastructure component.
+/// </summary>
+public static class ServiceCollectionExtensions
+{
+    /// <summary>
+    /// Registers the Cluster Infrastructure services. This component owns the
+    /// cluster <em>configuration contract</em> (<see cref="ClusterOptions"/>); the
+    /// Akka.NET bootstrap itself lives in <c>ZB.MOM.WW.ScadaBridge.Host</c>
+    /// (see <c>Component-ClusterInfrastructure.md</c>).
+    /// <para>
+    /// Registering the <see cref="ClusterOptionsValidator"/> means a misconfigured
+    /// <c>ScadaBridge:Cluster</c> section (e.g. <c>MinNrOfMembers: 2</c> or a quorum
+    /// split-brain strategy) throws an <see cref="OptionsValidationException"/> the
+    /// first time <see cref="IOptions{TOptions}"/> is resolved, rather than booting
+    /// into a broken cluster.
+    /// </para>
+    /// </summary>
+    /// <param name="services">The service collection to register into.</param>
+    public static IServiceCollection AddClusterInfrastructure(this IServiceCollection services)
+    {
+        services.TryAddEnumerable(
+            ServiceDescriptor.Singleton<IValidateOptions<ClusterOptions>, ClusterOptionsValidator>());
+        return services;
+    }
+
+    // ClusterInfra-014: the previous `AddClusterInfrastructureActors` extension
+    // was dead surface — its XML doc told callers "do not call", its body
+    // unconditionally threw `NotImplementedException`, and no production caller
+    // existed anywhere in the solution (verified by grep). The CI-002
+    // "throw loudly" decision was made while CI-001's ownership question was
+    // still open; that question is now permanently settled by the
+    // "Implementation Note — Code Placement" section of
+    // Component-ClusterInfrastructure.md, which records that all actor wiring
+    // lives in ZB.MOM.WW.ScadaBridge.Host (AkkaHostedService). Keeping a public extension
+    // method that exists only to throw was API-surface noise that an IDE would
+    // still suggest via auto-complete, so the method and its companion
+    // `AddClusterInfrastructureActors_ThrowsRatherThanSilentlySucceeding` test
+    // were both removed.
+}