[Functionapp] Fix Azure/azure-cli-extensions#10029: az functionapp create: Fix transient 403 on content share creation

[Copilot]

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Related command

az functionapp create

Creating a function app immediately after provisioning a network-restricted storage account can fail when Azure Files share creation races storage firewall/VNet rule propagation. This change adds targeted retry handling for that transient 403 path and surfaces a more actionable final error if propagation still has not completed.

• Behavior change

  • Override functionapp create in the extension and wrap core content share creation with retry/backoff when the storage management call returns HTTP 403.
  • Preserve existing behavior for non-403 failures.

• Failure mode

  • If all retries are exhausted, raise a concise error that points to storage network rule propagation delay instead of a generic storage accessibility failure.

• Scope

  • Applies only to the content share creation path used by az functionapp create with network-restricted storage accounts.
  • No change to unrelated functionapp commands.

• Targeted coverage

  • Add unit tests for retry-on-403, no-retry on non-403, and the final propagated error message.

for delay in (5, 10, 20, 40):
    try:
        return create_file_share(...)
    except Exception as ex:
        if status_code(ex) != 403:
            raise
        time.sleep(delay)

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[azure-client-tools-bot-prd]

⚠️Azure CLI Extensions Breaking Change Test

⚠️functionapp

rule	cmd_name	rule_message	suggest_message
⚠️ 1001 - CmdAdd	functionapp create	cmd functionapp create added

[azure-client-tools-bot-prd]

Hi @copilot,
Please write the description of changes which can be perceived by customers into HISTORY.rst.
If you want to release a new extension version, please update the version in setup.py as well.