fix(nuxi): set allowSyntheticDefaultImports

[danielroe]

🔗 Linked issue

should probably have been included in #1824 🤦
see #1822

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

This PR covers the following errors that would be thrown up by a TS lib-check:

node_modules/pathe/dist/index.d.ts:1:8 - error TS1259: Module '"path"' can only be default-imported using the 'allowSyntheticDefaultImports' flag

1 import path from 'path';
         ~~~~

  node_modules/@types/node/path.d.ts:167:5
    167     export = path;
            ~~~~~~~~~~~~~~
    This module is declared with using 'export =', and can only be used with a default import when using the 'allowSyntheticDefaultImports' flag.

node_modules/rollup-plugin-visualizer/dist/plugin/index.d.ts:2:8 - error TS1259: Module '"/node_modules/open/index"' can only be default-imported using the 'allowSyntheticDefaultImports' flag

2 import opn from "open";
         ~~~

  node_modules/open/index.d.ts:88:1
    88 export = open;
       ~~~~~~~~~~~~~~
    This module is declared with using 'export =', and can only be used with a default import when using the 'allowSyntheticDefaultImports' flag.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

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