Fold the single-caller network adapter predicates into their caller

[DireDoch]

src/Config-Network.ps1 splits adapter selection across three functions. Two of
them have one caller each:

Function	Lines	Real logic	Callers
Test-WcdNetworkAdapterActive	22	one regex, ^(Up|Connected)$	1
Get-WcdActiveNetworkAdapters	26	one Where-Object	1
Test-WcdRelevantNetworkAdapter	35	the virtual-adapter exclusion list	1

Apply the deletion test to the first two: inline them and complexity moves, it
does not concentrate. One caller each. They were extracted to be testable, not
because anything else needed them.

The third is different. That exclusion pattern — bluetooth|loopback|isatap| teredo|vmware|hyper-v|vEthernet|virtual|vpn|wan miniport|miniport|pangp| anyconnect|juniper|tap — is the real domain knowledge in this file, and it is
the thing that will actually be edited when a site's VPN client shows up in the
summary and shouldn't. Right now it is buried between two functions that do
nothing.

Note the tax

Every named function here costs ~20 lines of comment-based help, because
tests/Help.Tests.ps1 requires a synopsis, an example and a documented
parameter on all of them. That is the right rule for a Module's entry point and
an expensive one for a one-line predicate. Worth knowing when deciding whether
the next helper deserves a name.

What changes

• Fold Test-WcdNetworkAdapterActive into Get-WcdActiveNetworkAdapters
• Promote the exclusion pattern to a named script-scope variable at the top of
  the file, where someone looking for it will find it
• Keep Test-WcdRelevantNetworkAdapter as the function the test targets

Honestly: low priority

Small win, real churn, and the current shape is not hurting anyone. Filed
because it is the clearest example of the pattern in the repo. Take it if you
are already working in Config-Network.ps1; do not make a trip for it.

Done when

• Test-WcdNetworkAdapterActive folded into its caller
• Exclusion pattern named and visible at the top of the file
• tests/Config-Network.Tests.ps1 still covers the exclusion behaviour directly
• Same adapters selected before and after

[DireDoch]

Fait dans 82d9d82 (PR #32).

Un ecart avec l'issue: Test-WcdNetworkAdapterActive avait deux appelants, pas un — Config-Network.ps1:113 (le Where-Object de Get-WcdActiveNetworkAdapters) et :519 (la branche Wi-Fi de Set-WcdNetworkDiagnostics). Le regex ^(Up|Connected)$ est ecrit aux deux, et les 22 lignes de fonction + aide ont disparu.

Le motif d'exclusion est maintenant $script:WcdIrrelevantAdapterPattern en haut du fichier. tests/Config-Network.Tests.ps1 gagne trois tests qui visent l'exclusion directement plutot qu'a travers une execution complete, plus un qui epingle la combinaison actif-et-pertinent que l'inlining touchait.