deps: unpin Tailwind 4.1.18 once 4.2.2 ESM cache-loader bug is fixed upstream

[williamzujkowski]

Context

apps/web/package.json currently pins both tailwindcss and @tailwindcss/vite to exactly `4.1.18` (no caret). The pin was introduced in commit 4fff6e8 / PR #155 because `@tailwindcss/vite` 4.2.2 had a broken ESM chunk resolution that crashed Astro builds during prerendering.

Latest released is `4.3.0`. Need to verify whether the upstream bug is fixed before unpinning.

Verification checklist

• Reproduce the failure mode that PR bug: Astro build fails with Tailwind CSS 4.2.2 ESM chunk resolution error #153/fix: pin Tailwind CSS to 4.1.18 to fix ESM chunk resolution #155 originally hit on `4.2.2` (sanity check that current pin still avoids it).
• Build `apps/web` on `4.3.x` against the full content-data submodule (CI-equivalent, not the sparse local checkout).
• Compare `dist/` output between pinned-`4.1.18` and `4.3.x` — only expect CSS-file hash changes, no missing chunks.
• Spot-check a few rendered statute pages for layout regressions.

If 4.3.x passes: bump to `^4.3.0` (caret) in apps/web/package.json for both packages, regen lockfile.

If 4.3.x still hits the issue: leave pinned, comment with the upstream issue link.

Notes

Surfaced in the May 2026 cleanup session.