chore(deps): update dependency polyfill to 9.15.0

[thomhurst]

This PR contains the following updates:

Package	Type	Update	Change
Polyfill	nuget	minor	9.14.0 → 9.15.0

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Release Notes

SimonCropp/Polyfill (Polyfill)

v9.15.0

Compare Source

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Enabled.

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This PR has been generated by Renovate Bot.

[claude]

Code Review: Dependency Update - Polyfill 9.14.0 → 9.15.0

This is a straightforward minor version bump for the Polyfill package from 9.14.0 to 9.15.0.

Assessment: Approved ✓

Change: Single line in Directory.Packages.props updating the centrally managed package version.

Risk: Low. This is a minor version bump, so no breaking changes are expected per semantic versioning conventions.

Architecture: Using Directory.Packages.props for centralized package version management is the correct pattern — this single change propagates to all projects consuming the package, which is exactly how it should work.

Polyfill package context: The Polyfill library provides polyfills for APIs not available in older target frameworks (e.g., net8.0 in this repo's multi-targeting setup). Minor updates typically add new polyfills for newer APIs, making them available on older frameworks.

No issues found. The automated Renovate bot PR is well-structured and the auto-merge configuration is appropriate for low-risk dependency updates like this.