Fix/houdini22 interactive render settings

[gripeyes]

Compatibility:

patch

Issues/Tickets:

OpenMoonRay/openmoonray#276
#14

Release notes comment:

Fixed interactive render-settings updates in the Houdini 22 Solaris viewport.

Comments for the reviewer:

This PR is stacked directly on the head of #14 (85e63fc), Rob’s hdm_10 branch. Once #14 merges into main, this PR will contain only the interactive render-settings commit.

Houdini 22 identifies Solaris viewport renders with the houdini:viewport setting, while older versions used houdini:interactive. An active RenderSettings prim is also present during viewport rendering, so its presence alone cannot select the one-shot product-render path.

This change:

• recognizes both houdini:viewport and houdini:interactive
• applies client render settings before choosing the render path
• keeps Solaris viewport rendering on the interactive render-pass path
• tracks RenderSettings prim synchronization versions
• clears product-render completion when settings, products or renderer updates change
• preserves the one-shot path for actual offline product renders

Unrelated trailing whitespace changes from the validation commit were removed.

Umbrella validation PR:
OpenMoonRay/openmoonray#276

Houdini 22 build notes:
https://github.com/gripeyes/openmoonray/blob/test/houdini22-clean-build/building/macOS/Houdini22_build_notes.md

Look or scene setup change:

No expected look change. Render-setting edits now propagate correctly during interactive Solaris rendering.

Special notes for production:

Depends on the HdMoonray 10/Hydra 2.0 work in #14.

Attention/Reviewers:

@robwilson-dwa

AI Assisted Development:

Assisted-by: OpenAI Codex / GPT-5.6

Checklist:

• Documentation has been updated.
• Includes new unit tests.
• Includes new RATS tests.