[Update] Pipes and Filters sample refresh

[Federico Arambarri (CLARIUS CONSULTING SA) (v-federicoar)]

Summary

This PR updates the pipes-and-filters sample to keep the implementation current while preserving behavior.

What changed

• Replaced SixLabors.ImageSharp with SkiaSharp (MIT license) for image processing in Resize.cs and Watermark.cs.
• Added SkiaSharp and SkiaSharp.NativeAssets.Linux.NoDependencies packages.
• Simplified Program.cs by removing the IFileProvider / ManifestEmbeddedFileProvider registration (no longer needed).
• Changed resources/watermark.png from an embedded resource to regular content copied to the output directory.

Why

Starting with version 4.0, SixLabors.ImageSharp adopted a split license model that requires a commercial or community license key to build. The community license is free for open-source projects but expires periodically, requiring manual renewal. To avoid ongoing license maintenance in a sample repository, the image processing was migrated to SkiaSharp, which is MIT-licensed with no build-time license enforcement.

Addressing #513

Validation

• Built the updated Functions project successfully.
• Tested the example end-to-end:
  • Uploaded source image to blob storage.
  • Triggered pipeline via queue message.
  • Observed Resize, Watermark, and PublishFinal filters execute in sequence.
  • Confirmed processed image output is resized to 600px max and has a watermark overlay.

[Copilot]

Pull request overview

This PR migrates the pipes-and-filters image processing sample from SixLabors.ImageSharp (which now requires a license key) to SkiaSharp (MIT-licensed), updating the Resize and Watermark Azure Functions accordingly. The embedded resource approach for the watermark file is replaced with a simpler file-copy-to-output pattern, and the Bicep infrastructure template gets an API version bump.

Changes:

• Replaced SixLabors.ImageSharp with SkiaSharp for image resize and watermark operations, including added validation, error handling, and SkiaSharp-specific stream buffering.
• Removed IFileProvider/ManifestEmbeddedFileProvider infrastructure (DI registration, package, csproj settings) in favor of loading the watermark from the output directory via Path.Combine.
• Updated the Azure Storage account Bicep API version from 2025-06-01 to 2026-04-01.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
ImageProcessingPipeline.csproj	Swaps ImageSharp + embedded file provider packages for SkiaSharp; changes watermark from embedded resource to content file.
Resize.cs	Replaces ImageSharp resize logic with SkiaSharp; adds error handling try/catch and image validation.
Watermark.cs	Replaces ImageSharp watermark logic with SkiaSharp; loads watermark from disk instead of embedded resources; adds validation.
Program.cs	Removes IFileProvider DI registration and unused using directives.
main.bicep	Bumps Storage Account API version to 2026-04-01.

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[Chad Kittel (ckittel)]

Good conversion choice, IMO. Just one style question, but the rest looks good from my perspective.

[Chad Kittel (ckittel)]

Thanks for jumping on this. I moved the AzDO workitem for this into the current sprint so you can close it out when wrapped up.