Rename the CONTEXT.md terms that drifted inside the implementation

[DireDoch]

CONTEXT.md lists the words this project does not use. The interface honours
them. The implementation does not.

In the code	CONTEXT.md says	Where
$deviceResult	Form Factor (Avoid: DeviceType)	Resolve-WcdExecutionOptions
$usageResult, $usageLabel	Environment (Avoid: Usage)	Resolve-WcdExecutionOptions
$engineerResult, $engineerTypes, $engineerYesNo	Optional Tool (Avoid: engineer tool)	Resolve-WcdExecutionOptions
$T.PromptUsageDesc1, $T.PromptUsageDesc2	Environment	both $T tables
$T.PromptEngineer, $T.PromptEngineerDesc1/2, $T.EngineerBoxTitle, $T.EngineerCombineHint	Optional Tool	both $T tables
Etapes, Echecs, Avertissements	Steps, failures, warnings	the $moduleStatus object

The last row is its own problem: those are the only French identifiers in an
otherwise English codebase, on an object the Diagnostic reads by property name.

This is not cosmetic. Someone — or something — reading CONTEXT.md and then
grepping for Environment finds the parameter and the manifest key and stops,
because the value is called $usageResult from the moment it is read. The
domain language holds at the edge and breaks two lines in.

Also rename

ConvertTo-WcdOptionalToolSelection and Read-WcdOptionalToolChoice are already
correct — the drift is only in the locals and the $T keys around them. Fix
those and the file reads consistently.

Make it stick

tests/Help.Tests.ps1 already has a stale-vocabulary test:

Select-String -Pattern 'DeviceType|Config-Usage|Config-Engineer|Minimal[A-Z]'

Extend the pattern to the words above so the drift cannot come back. That test
is the actual deliverable — the rename without it just resets the clock.

Note the pattern must not catch legitimate uses: Get-WcdPnPDevices and
Config-DeviceManager contain "Device", and Set-WcdDeviceManagerStatus is a
correct name. Anchor on the specific identifiers, not on substrings.

Done when

• Locals in Resolve-WcdExecutionOptions renamed to Form Factor / Environment / Optional Tool
• $T keys renamed in both language tables
• $moduleStatus fields renamed to English; every reader updated
  (Format-WcdModuleLine, Get-WcdFinalDiagnosticLines, the run loop)
• tests/Help.Tests.ps1 stale-vocabulary pattern extended
• The extended pattern does not flag Config-DeviceManager or Get-WcdPnPDevices
• Full suite green; no behaviour change

[DireDoch]

Fait dans 91d5921 (PR #32).

Renommes: les locaux de Resolve-WcdExecutionOptions, les cles $T dans les deux tables, et les trois identifiants francais de $moduleStatus (Etapes/Echecs/Avertissements -> Steps/Failures/Warnings). Format-WcdModuleLine etait leur seul lecteur.

Deux precisions par rapport a l'issue:

• Les quatre autres cles Engineer* (ChoicePrompt, AtLeastOne, InvalidChoice, Selection) sont renommees aussi. Sans ca le motif de garde ne pouvait pas s'ancrer dessus et la moitie de la derive restait.
• Les chaines affichees en anglais disent toujours "Engineering workstation" — c'est de l'anglais correct pour le technicien, seules les cles etaient fautives.

Le garde est le vrai livrable: le motif est construit une fois dans BeforeAll et sert deux fois — balayer src/*.ps1, et verifier qu'il ne signale pas Config-DeviceManager, Get-WcdPnPDevices, Set-WcdDeviceManagerStatus ni les chaines FR 'Echecs: {0}' / 'Avertissements: {0}'. Verifie en reintroduisant $deviceResult, la cle Etapes et $ModuleStatus.Etapes un par un: chacun fait echouer le test.

A noter au passage: Failures et Warnings sont ecrits mais jamais lus. Renommes tels quels puisque l'issue demandait un renommage sans changement de comportement — a supprimer si personne ne leur trouve un lecteur.