Update for trusted publishing

[delucis]

This PR:

• Updates the pnpm version — this repo was on v7 (!)
• Updates the publishing workflow to work with OIDC trusted publishing
• Fixes a type error (showed up because Typescript was updated 5.2.2 => 5.9.3 when I updated pnpm and recreated the lock file)

Todo:

• Update https://www.npmjs.com/package/@astrojs/cli-kit settings to point to ci.yml in withastro/cli-kit
• Add a changeset? I like doing this to ensure we go through the full publishing flow and verify things are working (especially for a package like this we publish rarely), but I know @matthewp doesn’t agree.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 6c43750

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