…, wire OpenAI location

Mirror the .NET sample cleanup in the Python sample:
- Remove the VNet module (AKS auto-provisions a managed VNet) and delete
  the unused vnet.bicep
- Fix stale gpt-4o references to gpt-5.1 to match the infra default
- Wire AZURE_OPENAI_LOCATION in main.parameters.json (defaults to eastus)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…default version

AKS 1.32 moved to Long-Term Support only, so pinning it fails preflight
validation on non-Premium clusters with K8sVersionNotSupported. Default
kubernetesVersion to empty in both samples and omit the property when
unset so AKS provisions its current default supported version.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

List the supported preview regions (East US 2, West US 3, North Europe,
Australia East, South Africa North) in the overview "Get private preview
access" section, reference them from Get started, and note the region
requirement in both sample READMEs.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…ions

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…ipts POSIX

azd only supports sh/pwsh/python/js/ts for hook shells; 'bash' fails with
"kind is not supported". Switch the predeploy/postprovision hooks to
shell: sh in both samples and drop the non-POSIX 'pipefail' option from the
hook scripts so they run under a POSIX sh.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

durabletask-azuremanaged==1.6.0 already depends on durabletask>=1.6.0, so
pip resolves the core SDK transitively. Remove the explicit durabletask==1.6.0
from the guide, sample requirements.txt, Containerfiles, and the sample README.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

… add Windows hooks

- Remove redundant FROM --platform=$TARGETPLATFORM from .NET Containerfiles (ACR classic builder doesn't support it; --platform on az acr build already sets it)
- Pass --build-arg TARGETARCH=amd64 in dotnet acr-build.sh (classic builder doesn't auto-populate BuildKit TARGETARCH)
- Add Windows PowerShell ports of acr-build and attach-scheduler-identity scripts for dotnet and python
- Convert azure.yaml predeploy/postprovision hooks to per-OS (posix: sh, windows: pwsh)

The main-app scheduled a single orchestration then exited. Deployed as a
Deployment, Kubernetes restarted the pod on every exit and re-scheduled a new
orchestration each time. Idle after the single run instead of exiting so the pod
stays Running:
- .NET: await host.WaitForShutdownAsync() instead of StopAsync()+return
- Python: idle loop inside the worker context until SIGTERM/Ctrl+C

…ll guidance

- Label the top prerequisites as local development and the azd ones as Azure deployment
- Replace contradictory 'enable anonymous pull' steps with granting the image-pull
  managed identity AcrPull (matches the code's required DTS_SANDBOX_IMAGE_PULL_UMI_CLIENT_ID
  and the bicep, which sets anonymousPullEnabled=false)
- Refresh example chat models (GPT-5.1/5/4.1); add Azure CLI + the two UMIs to .NET prereqs