Prepare durabletask 1.9.0 and Azure Functions 2.0.0b2 releases

[andystaples]

Summary

• prepare durabletask 1.9.0, durabletask.azuremanaged 1.9.0, and azure-functions-durable 2.0.0b2
• move the accumulated unreleased notes under versioned release headings
• add callouts for core replay and serialization performance, Azure Managed sandbox startup and recovery performance, and Azure Functions compatibility and inherited core improvements

Commit coverage

• durabletask: v1.8.0..HEAD
• durabletask.azuremanaged: azuremanaged-v1.8.0..HEAD
• azure-functions-durable: azurefunctions-v2.0.0b1..HEAD

The Azure Functions range uses the repository's prior package release tag, azurefunctions-v2.0.0b1.

Validation

• parsed all three pyproject.toml files and verified package versions and dependency floors
• checked the release headings and final diff formatting

[Copilot]

Pull request overview

Prepares the durabletask 1.9.0, durabletask.azuremanaged 1.9.0, and azure-functions-durable 2.0.0b2 releases by bumping package versions/dependency floors and moving accumulated “Unreleased” notes under versioned release headings across the three package changelogs.

Changes:

• Bumped package versions for durabletask.azuremanaged to 1.9.0 and azure-functions-durable to 2.0.0b2 (and aligned minimum durabletask dependency where applicable).
• Promoted “Unreleased” changelog entries into versioned v1.9.0 / v2.0.0b2 sections.
• Added release callouts describing performance improvements and compatibility notes.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
durabletask-azuremanaged/pyproject.toml	Bumps durabletask.azuremanaged version to 1.9.0 and raises the minimum durabletask dependency to 1.9.0.
durabletask-azuremanaged/CHANGELOG.md	Moves accumulated notes into a new v1.9.0 release section.
CHANGELOG.md	Adds the v1.9.0 release heading and places changes under it for the core SDK.
azure-functions-durable/pyproject.toml	Bumps azure-functions-durable to 2.0.0b2.
azure-functions-durable/CHANGELOG.md	Adds the v2.0.0b2 release heading and includes notes about inherited durabletask 1.9.0 improvements.