fix(historian-gateway): wire dormant GatewayTagProvisioner + provisioning observability/docs

PR #423 shipped GatewayTagProvisioner + unit tests but never registered it in
DI nor passed it into the AddressSpaceApplier, so deploying historized tags used
the no-op NullHistorianProvisioning and never called the gateway's EnsureTags
(confirmed live on wonder-app-vd03: zero EnsureTags calls on a historized deploy).
Addresses HISTORIAN-GATEWAY-INTEGRATION-ISSUES.md.

Issue 1 (wire provisioner):
- Runtime: AddHistorianProvisioning extension (gated on ServerHistorian:Enabled,
  mirrors AddServerHistorian) + NullHistorianProvisioning TryAdd default in
  AddOtOpcUaRuntime; WithOtOpcUaRuntimeActors resolves IHistorianProvisioning and
  passes it into the applier.
- Gateway driver: GatewayHistorian.CreateProvisioner factory (mirrors CreateDataSource).
- Host: Program.cs calls AddHistorianProvisioning after AddServerHistorian.
- Tests: AddHistorianProvisioningTests (config-gated registration + the
  register->resolve->applier->EnsureTags chain).

Issue 2 (observability): AddressSpaceApplier logs the provisioning tally on every
successful dispatch (was gated behind Failed/Skipped > 0), including dispatched=N
so a dispatched=N/requested=0 line flags the dormant no-op. +2 tests.

Issue 3 (30s HistoryRead on unprovisioned tags): root coupling fixed by Issue 1;
documented the CallTimeout knob + coupling. Default left at 30s pending the
multi-data-point investigation the issue requests (lowering risks truncating
legitimate large reads).

Issue 4 (docs): docs/Historian.md gains a "Tag auto-provisioning (EnsureTags)"
section and CLAUDE.md a wiring/gating note (both stress ServerHistorian:Enabled).
Sibling scadaproj/CLAUDE.md carries no false claim -> unchanged.

Pre-existing Serilog observation: anchor CWD to AppContext.BaseDirectory before
AddZbSerilog so the relative file sink stops landing in C:\Windows\System32 under
the Windows-service CWD.

Builds 0-error; Runtime.Tests 355, OpcUaServer.Tests 329, Gateway.Tests 99 (+4
live-skipped) all green.

src/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer/AddressSpaceApplier.cs

@@ -271,13 +271,15 @@ public sealed class AddressSpaceApplier
                         return;
                     }
 
+                    // Emit a tally on EVERY successful dispatch (not only on Failed/Skipped) so a fully-
+                    // successful provisioning is observable AND a dormant no-op is detectable: the no-op
+                    // NullHistorianProvisioning reports Requested=0 regardless of input, so a line showing
+                    // dispatched={N} but requested=0 unmistakably flags "provisioning is not wired" — the
+                    // exact invisibility that let the dormant-provisioner bug ship unnoticed.
                     var result = t.Result;
-                    if (result.Failed > 0 || result.Skipped > 0)
-                    {
-                        _logger.LogInformation(
-                            "AddressSpaceApplier: historian provisioning completed (requested={Requested}, ensured={Ensured}, skipped={Skipped}, failed={Failed})",
-                            result.Requested, result.Ensured, result.Skipped, result.Failed);
-                    }
+                    _logger.LogInformation(
+                        "AddressSpaceApplier: historian provisioning completed (dispatched={Dispatched}, requested={Requested}, ensured={Ensured}, skipped={Skipped}, failed={Failed})",
+                        provisionCount, result.Requested, result.Ensured, result.Skipped, result.Failed);
                 },
                 CancellationToken.None,
                 TaskContinuationOptions.None,