feat(focas): OtOpcUa-owned otopcua-focas-fixture stack (#651) + FOCAS backlog docs (#633)

Fixture renamed off ignitionoee's otopcua-focas-sim, port 8193 published, project label,
default endpoint 10.100.0.35:8193; infra/dev-environment docs. FOCAS.md: MACRO:3901 parts
count, PMC override + cycle-time recipes, won't-do/blocked backlog.

Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe

scripts/integration/run-focas.ps1

@@ -106,6 +106,8 @@ else {
 
 Write-Step "dotnet test (wire-backend integration)"
 $env:OTOPCUA_FOCAS_SIM_PROFILE = $Profile
+# The fixture default is the shared Docker host (10.100.0.35:8193); this script runs the mock locally.
+if (-not $env:OTOPCUA_FOCAS_SIM_ENDPOINT) { $env:OTOPCUA_FOCAS_SIM_ENDPOINT = "localhost:8193" }
 
 dotnet test (Join-Path $integTests "ZB.MOM.WW.OtOpcUa.Driver.FOCAS.IntegrationTests.csproj") `
     --configuration $Configuration --no-build --nologo --verbosity minimal