Create the windows of the samples from the container instead of with new()

[romanett]

Closes #813.

The problem

A sample form was created by the container, but everything it opened was not. A control
called new SomeDlg() and then handed the dialog what it needed through the arguments of
ShowDialog:

string endpointUrl = new DiscoverServerDlg().ShowDialog(Configuration, hostName, m_telemetry);

The dependencies of a window were therefore the business of whoever opened it, which is why
ITelemetryContext, ApplicationConfiguration and ILogger were threaded through nearly
every show method in the repository - 212 construction sites across 185 form and control
classes.

What this does

Samples/WinForms.Common (Opc.Ua.Samples.WinForms) carries the plumbing:
IWindowFactory.Create<TWindow>() builds a window out of the container - what the caller
passes is matched to the constructor by type, the rest is resolved as services - and hands
itself to what it created, so a dialog can open the next one.

// DiscoverServerDlg(ITelemetryContext telemetry)
string endpointUrl = Windows.Create<DiscoverServerDlg>().ShowDialog(Configuration, hostName);

The Windows Forms designer writes new SomeCtrl() into the generated code of a form, so a
control cannot take the factory through its constructor. SampleForm and
SampleUserControl expose it as Windows, and the form the container created hands it down
its control tree once; a control parented later finds it by walking up. A control on neither
says so rather than failing with a null reference. See
the README.

With that in place:

• Opc.Ua.ClientControls, Opc.Ua.SampleControls, Opc.Ua.ServerControls, the global
  discovery client controls and every sample and Workshop application create their windows
  through the factory, and their dialogs take the telemetry, the configuration and their
  logger through their constructors.
• ServerForm has one container constructor plus ServerFormOptions, which replaces
  ServerForm.Create(IServiceProvider) and the two hand written provider factories the
  reference server and the global discovery server had. The 18 Workshop servers are plain
  SampleWinFormsHost.Run<ServerForm> now.
• ClientForm and SampleClientForm lost the ServiceMessageContext and the master
  form from their constructors - the first is derived from the configuration, the second is
  what OpenForm sets on the window it opens - so Client.Net4 has no form factory either.
• The message box the stack asks its questions through was a class copied into the client
  controls and the server controls and installed by hand in 45 entry points. It is a
  registration, and the entry point helper installs it before the host starts.
• The reference client got a composition root (AddReferenceClient()), so the listener
  its Server menu arms comes from the container rather than out of the window's own fields.
• ~100 CA2000 suppressions whose justification was the undisposed new SomeDlg() are
  gone with it.

Two windows are deliberately still constructed by hand: ExceptionDlg, which reports
failures of the sample including a failure to build the container, and the console samples'
own message dialog.

Testing

All five tiers pass, on the tree as it stands:

Tier	Result
0 - Configuration	237 passed
1 - Server smoke	121 passed
1.5 - Node managers	178 passed, 4 skipped
1.7 - Client models	420 passed, 4 skipped
2 - Client smoke	65 passed

Tier 2 now builds its forms through the factory too, so what it covers is the wiring of the
samples rather than a second copy of it written in the test; a test which assembles a form
out of single controls hands them a factory through the new TestWindowFactory.

dotnet build of the solution and of all four .sln files is clean, with the same warning
set as master.

🤖 Generated with Claude Code