Update OpenRouter model handling and enhance documentation

[nblog]

Enhance the handling of the OpenRouter model and improve related documentation for better clarity and usability.

[Copilot]

Pull request overview

Updates the nano-banana-pro-openrouter skill to make the OpenRouter model configurable at runtime and refreshes the skill documentation to clarify default behavior.

Changes:

• Add a DEFAULT_MODEL constant and a --model CLI option to override the OpenRouter model used for image generation.
• Update SKILL.md to clarify the default model and document model selection.

Reviewed changes

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

File	Description
skills/nano-banana-pro-openrouter/SKILL.md	Updates overview text and adds a “Model selection” section; adjusts frontmatter description wording.
skills/nano-banana-pro-openrouter/scripts/generate_image.py	Introduces DEFAULT_MODEL, adds --model argument, and wires it into the OpenRouter request.

[aaronpowell]

It looks like you've incorrectly branched from the main branch not staged, and as a result all the materialised plugins are included in this PR.

You can attempt to fix this with a rebase:

git fetch origin staged
git rebase --onto origin/staged origin/main <branch name>
git push --force-with-lease

If that does not resolve it, you can run npm run plugin:clean which will delete the materialised plugins and you can commit that change.

[nblog]

@aaronpowell Thanks for the review and guidance.
I have rebuilt this PR branch from upstream/staged, restored only the intended changes under skills/nano-banana-pro-openrouter, and force-pushed the cleaned branch.

The diff should now contain only these two files:

• skills/nano-banana-pro-openrouter/SKILL.md
• skills/nano-banana-pro-openrouter/scripts/generate_image.py

Could you please take another look when you have a moment?