Fix manuscript rendering blocking on git remote errors

[cderv]

When rendering manuscript projects with git origin pointing to a private repository, Quarto prompts for GitHub credentials or fails with an error:

Username for 'https://github.com': 
Password for 'https://...@github.com':

or

ERROR: There is an error while retrieving information from remote 'origin'.
 Git error: git@github.com: Permission denied (publickey).
...

This blocks renders and prevents users from working with manuscript projects that have private repositories as their git origin.

Root Cause

The manuscript project type calls gitHubContext() in filterParams() to auto-detect the manuscript-url from GitHub Pages. This function runs git ls-remote origin gh-pages, which is a network operation requiring authentication for private repos. Any failure (credentials, network, host key verification, repository not found) throws an error that blocks rendering.

Fix

Added try/catch in manuscript.ts filterParams() around the gitHubContext() call (line 371). When git operations fail:

• Error is caught gracefully without blocking the render
• Warning shown once per render using warnOnce(): "Unable to auto-detect manuscript URL from GitHub Pages. Set manuscript-url explicitly in your configuration if needed."
• Full error details logged when --log-level debug is used
• Conditional debug hint added to warning message in non-debug mode
• Properly typed error handling for TypeScript

The fix only modifies manuscript.ts - github.ts remains unchanged so publish workflows continue to receive thrown errors as expected.

Manual Testing

Tested with manuscript-tutorial repository by changing origin to point to non-existent private repository:

cd /tmp
git clone https://github.com/cderv/manuscript-tutorial
cd manuscript-tutorial
git remote set-url origin https://github.com/cderv/private-manuscript-repo.git
quarto render

Verified:

• ✅ Rendering completes successfully without prompting for credentials
• ✅ Warning appears once (not repeated for every file): "WARN: Unable to auto-detect manuscript URL from GitHub Pages..."
• ✅ Debug mode shows full error details: "Failed to auto-detect manuscript URL from GitHub: There is an error while retrieving information from remote 'origin'..."
• ✅ Warning includes debug hint in normal mode, excludes it in debug mode
• ✅ Output created successfully: _manuscript/index.html

Fixes #10031

[posit-snyk-bot]

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