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.Commons/Entities/ExternalSystems/ExternalSystemMethod.cs

@@ -0,0 +1,33 @@
+namespace ZB.MOM.WW.ScadaBridge.Commons.Entities.ExternalSystems;
+
+/// <summary>
+/// Defines a callable HTTP method on an external system definition.
+/// </summary>
+public class ExternalSystemMethod
+{
+    /// <summary>Primary key.</summary>
+    public int Id { get; set; }
+    /// <summary>Foreign key referencing the owning <c>ExternalSystemDefinition</c>.</summary>
+    public int ExternalSystemDefinitionId { get; set; }
+    /// <summary>Name of the method as referenced in scripts.</summary>
+    public string Name { get; set; }
+    /// <summary>HTTP method (GET, POST, PUT, DELETE, etc.).</summary>
+    public string HttpMethod { get; set; }
+    /// <summary>URL path relative to the external system's base URL.</summary>
+    public string Path { get; set; }
+    /// <summary>JSON-serialized parameter definitions for this method, or null if there are none.</summary>
+    public string? ParameterDefinitions { get; set; }
+    /// <summary>JSON-serialized return type definition for this method, or null if void.</summary>
+    public string? ReturnDefinition { get; set; }
+
+    /// <summary>Initializes a new instance of <see cref="ExternalSystemMethod"/> with the required fields.</summary>
+    /// <param name="name">The method name.</param>
+    /// <param name="httpMethod">The HTTP method verb.</param>
+    /// <param name="path">The URL path.</param>
+    public ExternalSystemMethod(string name, string httpMethod, string path)
+    {
+        Name = name ?? throw new ArgumentNullException(nameof(name));
+        HttpMethod = httpMethod ?? throw new ArgumentNullException(nameof(httpMethod));
+        Path = path ?? throw new ArgumentNullException(nameof(path));
+    }
+}