chore: migrate workspace tooling to repoctl 5.4.4

[sonofmagic]

Summary

• migrate the workspace from the legacy monorepo CLI/config to repoctl 5.4.4
• move managed tooling configs to repoctl/tooling
• adopt repoctl release v2 workflow and pnpm repository changelog versioning
• preserve PostCSS project-specific docs, Dockerfile, and unbuild package scaffold defaults

Verification

• pnpm install --frozen-lockfile
• pnpm exec repo doctor
• pnpm exec repo check
• pnpm run build
• pnpm run lint
• pnpm run typecheck
• pnpm run test
• pnpm run check:cjs

All checks pass; lint reports the existing non-blocking ts/no-use-before-define warning in packages/postcss-plugin-shared/src/selectors.ts.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 5ef637d

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