Publish snapshot: image editor suite, Krea 2 templates, sidebar fixes

- Image editor: layers with masks/blend modes, lightweight groups, Camera Raw
  scoped to the selected layer, full-frame i2i, Copy Merged, Photoshop keyboard
  shortcuts, and a large batch of Photoshop-parity bug fixes.
- LoadImage right-click "Open in PromptChain editor" bridge (edit -> lineage
  child re-pointed onto the node).
- Krea 2 Turbo/Realism templates and editor modal integration; remove the
  krea2 Text-to-Image 3D Regional template.
- ControlNet depth + 3D-pose: wire Poser true-depth straight into Apply
  ControlNet on pose paths.
- Sidebar: drag-to-LoadImage now uploads to the input root so the widget value
  is a valid bare filename; "Copy as path" emits native Windows backslashes.
- Contributor/relicensing docs and packaging tweaks.

.github/PULL_REQUEST_TEMPLATE.md

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+> **By opening this pull request, I agree to the terms in
+> [CONTRIBUTING.md](../CONTRIBUTING.md)** — including the grant that lets the
+> maintainer relicense my contribution (for example, under the MIT License).
+
+<!-- The line above is the contributor agreement; please leave it in place. -->
+
+## What does this PR do?
+
+
+## Related issues
+
+
+## Checklist
+
+- [ ] I have read and agree to [CONTRIBUTING.md](../CONTRIBUTING.md).