fix: openrouter filters out non llm models by default

[lukasdotcom]

Noticed that openrouter filters models by modalities (https://openrouter.ai/docs/guides/overview/models#output_modalities) this could actually be useful for only showing the right image, tts, etc models, but sadly seems to only be openrouter specific.

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• The content of this PR was partly or fully generated using AI

[lukasdotcom]

/backport to stable32

[backportbot]

The backport to stable32 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable32
git pull origin stable32

# Create the new backport branch
git checkout -b backport/404/stable32

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick a3d53b22

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/404/stable32

Error: Failed to check for changes with origin/stable32: No changes found in backport branch

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Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.