fix: use config.consumer instead of options?.ssr / config.build.ssr

[sapphi-red]

Description

Replaced options?.ssr and config.build.ssr with config.consumer === 'server'.

I didn't actually face any issues but found it while reading the code.

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[patak-dev]

/ecosystem-ci run

[vite-ecosystem-ci]

📝 Ran ecosystem CI on c47392b: Open

suite	result	latest scheduled
histoire	❌ failure	❌ failure
remix	❌ failure	❌ failure
sveltekit	❌ failure	❌ failure
vike	❌ failure	❌ failure
vitest	✅ success	❌ failure

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