Improve publish error message when public network access is disabled

[Copilot]

Deployments to Function Apps with public network access disabled (now the portal default) fail with the cryptic The SSL connection could not be established, see inner exception. — no context, no remediation path.

Changes

• Constants.Errors.PublishNetworkingError — new constant with an actionable message pointing to https://learn.microsoft.com/azure/azure-functions/functions-networking-options
• PublishFunctionAppAction.RunAsync() — wraps PublishFunctionApp/PublishLocalAppSettings in a try/catch (HttpRequestException) that re-throws as CliException with the improved message + original error detail
• release_notes.md — added entry for this improvement referencing PR Improve publish error message when public network access is disabled #4807

HttpRequestException is only raised for transport-level failures (SSL, socket, DNS); HTTP 4xx/5xx are already caught upstream by CheckResponseStatusAsync as CliException, so this catch is scoped correctly.

Before:

The SSL connection could not be established, see inner exception.

After:

Unable to connect to the Azure Function App. If public network access is disabled for this app,
ensure you are deploying from an authorized network. For more information, see
https://learn.microsoft.com/azure/azure-functions/functions-networking-options
Details: The SSL connection could not be established, see inner exception.

Pull request checklist

• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes do not need to be backported to a previous version
  • Otherwise: Backport tracked by issue/PR #issue_or_pr
• My changes should not be added to the release notes for the next release
  • Otherwise: I've added my notes to release_notes.md
• I have added all required tests (Unit tests, E2E tests)

Additional information

The error message directs users to the official Azure Functions networking options documentation at https://learn.microsoft.com/azure/azure-functions/functions-networking-options, which covers VNet integration, private endpoints, and IP restrictions.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Publish action error message improvement</issue_title>
<issue_description>When public networking is disabled (which is now the default in the portal create flow), deployments from core tools fail with an unhelpful error message, just "see inner exception" with no actionable detail. It would be helpful to improve this message, perhaps by including an aka.ms link listing common deployment issues and their resolutions.

</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Publish action error message improvement #4570

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