ci: use org variable for CURSOR_PREFERRED_MODEL

[rgarcia]

Switches agent --model ${{ secrets.CURSOR_PREFERRED_MODEL }} to ${{ vars.CURSOR_PREFERRED_MODEL }} so the model value is visible in plaintext.

The org-wide variable CURSOR_PREFERRED_MODEL has been set to claude-opus-4-8-thinking-max.

Part of an org-wide migration of this key from secret to variable. The secret will be deleted once all repos are migrated.

🤖 Generated with Claude Code

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Note

Low Risk
Single workflow input change with no application or auth logic changes; model name exposure is intentional per org migration.

Overview
Updates the Fix CI Failures workflow so cursor-agent reads the preferred model from a GitHub organization variable (vars.CURSOR_PREFERRED_MODEL) instead of a secret (secrets.CURSOR_PREFERRED_MODEL).

This matches an org-wide move to store the model name in plaintext (e.g. claude-opus-4-8-thinking-max) while other credentials stay in secrets.

^{Reviewed by Cursor Bugbot for commit 6dd4fe1. Bugbot is set up for automated code reviews on this repo. Configure here.}

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