Stabilize Azure Functions Durable E2E tests

[andystaples]

Summary

• write history-export artifacts to the system temporary directory instead of beneath the Function app, preventing the Functions file watcher from restarting the host mid-suite
• temporarily skip the six E2E checks that directly depend on Azurite returning messages after an initial visibility delay: V1 and durabletask timers, delayed entity signals, and scheduled tasks
• centralize the skip explanation and link it to Queues do not correctly handle visibility timeout Azure/Azurite#2343 so the quarantine is easy to remove when emulator behavior is reliable

The AzureStorage polling interval does not address this failure: the failed runs polled after the messages were due, but Azurite returned empty queue responses. Retry-policy E2Es remain enabled because they have not exhibited the failure and use substantially shorter delays.

Validation

• python -m flake8 on the changed E2E files
• focused history-export Functions E2E: 2 passed
• full Functions E2E: 74 passed, 7 skipped (six quarantined tests plus the pre-existing Docker-dependent tracing skip)
• confirmed the Functions host log contains no configuration-change restart during history export

[Copilot]

Pull request overview

This PR stabilizes the Azure Functions Durable E2E test suite by preventing Functions host restarts during history export and quarantining a small set of flaky Azurite-dependent scenarios.

Changes:

• Write history-export artifacts to an OS temp directory (outside the Function app root) to avoid triggering the Functions file watcher.
• Quarantine the Azurite “delayed visibility” dependent E2Es via a centralized skip marker with a linked tracking issue.
• Apply the shared marker across the affected V1, durabletask, entity, and scheduled-task E2E tests.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/azure-functions-durable/e2e/test_v1_patterns_e2e.py	Skips the V1 timer E2E affected by Azurite delayed-visibility flakiness.
tests/azure-functions-durable/e2e/test_dtask_scheduled_e2e.py	Skips scheduled-task E2Es that depend on delayed queue message visibility.
tests/azure-functions-durable/e2e/test_dtask_patterns_e2e.py	Skips the durabletask-native timer E2E affected by delayed visibility.
tests/azure-functions-durable/e2e/test_dtask_entities_advanced_e2e.py	Skips delayed entity signal E2Es impacted by Azurite behavior.
tests/azure-functions-durable/e2e/apps/dtask_style/history_export_routes.py	Moves exported history output to a stable temp directory outside the app to prevent host restarts.
tests/azure-functions-durable/e2e/_markers.py	Adds a centralized, documented pytest skip marker for the Azurite delayed-visibility quarantine.

[berndverst]

Reviewed head 6d50cb0 against merge base 50f62e2. I found no actionable issues in the complete diff or affected Azure Functions E2E lifecycle and test infrastructure.