chore: add benchmarks

[ematipico]

Description

• Adds end-to-end build benchmarks — follow-up to chore: add benchmarks #4157 where we decided to only include functional benchmarks for now
• Currently there are issues with these build benchmarks. We need to switch to walltime measurement and are waiting on support to be releases for latest Vite/Vitest (one PR is merged but not released yet, the other still in draft).

[changeset-bot]

⚠️ No Changeset found

Latest commit: 056605c

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[astrobot-houston]

size-limit report 📦

Path	Size
/index.html	6.1 KB (0%)
/guides/example/index.html	6.02 KB (0%)
/_astro/*.js	25.44 KB (0%)
/_astro/*.css	14.72 KB (0%)

[codspeed]

Merging this PR will not alter performance

✅ 2 untouched benchmarks
🆕 3 new benchmarks

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
🆕	build	N/A	24.9 s	N/A
🆕	build	N/A	24.9 s	N/A
🆕	build	N/A	24.9 s	N/A

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_{Comparing wip/e2e-benchmarks (e2976a4) with main (cdfafd8)}