ci: upgrade to pnpm 9

[hanspagel]

Let’s use pnpm 9 in CI. :)

[changeset-bot]

⚠️ No Changeset found

Latest commit: a36205a

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[relativeci]

#99 Bundle Size — 114.47KiB (+0.01%).

a36205a(current) vs 21b6fc0 main#98(baseline)

Bundle metrics   2 changes 1 regression

	Current #99	Baseline #98
Initial JS	114.47KiB(+0.01%)	114.45KiB
Initial CSS	0B	0B
Cache Invalidation	1.66%	0%
Chunks	45	45
Assets	45	45
Modules	45	45
Duplicate Modules	0	0
Duplicate Code	0%	0%
Packages	0	0
Duplicate Packages	0	0

Bundle size by type   1 change 1 regression

	Current #99	Baseline #98
JS	114.47KiB (+0.01%)	114.45KiB

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Bundle analysis report Branch ci/pnpm-9 Project dashboard

[hanspagel]

Close in favor of #132.