chore: organize solution into module folders (Core/Server/Drivers/Client/Tooling)

Group all 69 projects into category subfolders under src/ and tests/ so the
Rider Solution Explorer mirrors the module structure. Folders: Core, Server,
Drivers (with a nested Driver CLIs subfolder), Client, Tooling.

- Move every project folder on disk with git mv (history preserved as renames).
- Recompute relative paths in 57 .csproj files: cross-category ProjectReferences,
  the lib/ HintPath+None refs in Driver.Historian.Wonderware, and the external
  mxaccessgw refs in Driver.Galaxy and its test project.
- Rebuild ZB.MOM.WW.OtOpcUa.slnx with nested solution folders.
- Re-prefix project paths in functional scripts (e2e, compliance, smoke SQL,
  integration, install).

Build green (0 errors); unit tests pass. Docs left for a separate pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/Core/ZB.MOM.WW.OtOpcUa.Configuration/Entities/Equipment.cs

@@ -0,0 +1,64 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     UNS level-5 entity. Only for drivers in Equipment-kind namespaces.
+///     Per decisions #109 (first-class), #116 (5-identifier model), #125 (system-generated EquipmentId),
+///     #138–139 (OPC 40010 Identification fields as first-class columns).
+/// </summary>
+public sealed class Equipment
+{
+    public Guid EquipmentRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    /// <summary>
+    ///     System-generated stable internal logical ID. Format: <c>'EQ-' + first 12 hex chars of EquipmentUuid</c>.
+    ///     NEVER operator-supplied, NEVER in CSV imports, NEVER editable in Admin UI (decision #125).
+    /// </summary>
+    public required string EquipmentId { get; set; }
+
+    /// <summary>UUIDv4, IMMUTABLE across all generations of the same EquipmentId. Downstream-consumer join key.</summary>
+    public Guid EquipmentUuid { get; set; }
+
+    /// <summary>Logical FK to the driver providing data for this equipment.</summary>
+    public required string DriverInstanceId { get; set; }
+
+    /// <summary>Optional logical FK to a multi-device driver's device.</summary>
+    public string? DeviceId { get; set; }
+
+    /// <summary>Logical FK to <see cref="UnsLine.UnsLineId"/>.</summary>
+    public required string UnsLineId { get; set; }
+
+    /// <summary>UNS level 5 segment, matches <c>^[a-z0-9-]{1,32}$</c>.</summary>
+    public required string Name { get; set; }
+
+    // Operator-facing / external-system identifiers (decision #116)
+
+    /// <summary>Operator colloquial id (e.g. "machine_001"). Unique within cluster. Required.</summary>
+    public required string MachineCode { get; set; }
+
+    /// <summary>ERP equipment id. Unique fleet-wide via <see cref="ExternalIdReservation"/>. Primary browse identifier in Admin UI.</summary>
+    public string? ZTag { get; set; }
+
+    /// <summary>SAP PM equipment id. Unique fleet-wide via <see cref="ExternalIdReservation"/>.</summary>
+    public string? SAPID { get; set; }
+
+    // OPC UA Companion Spec OPC 40010 Machinery Identification fields (decision #139).
+    // All nullable so equipment can be added before identity is fully captured.
+    public string? Manufacturer { get; set; }
+    public string? Model { get; set; }
+    public string? SerialNumber { get; set; }
+    public string? HardwareRevision { get; set; }
+    public string? SoftwareRevision { get; set; }
+    public short? YearOfConstruction { get; set; }
+    public string? AssetLocation { get; set; }
+    public string? ManufacturerUri { get; set; }
+    public string? DeviceManualUri { get; set; }
+
+    /// <summary>Nullable hook for future schemas-repo template ID (decision #112).</summary>
+    public string? EquipmentClassRef { get; set; }
+
+    public bool Enabled { get; set; } = true;
+
+    public ConfigGeneration? Generation { get; set; }
+}