Complete the engine 0.6.3 transition and remove dev-only conformance exceptions #333

Tracks the coordinated engine release for #332, following the transition used by #313 and cleaned up in #328.

• Merge fix(engine): allow ArkType to dedupe with ORM packages #332 and confirm @prisma/cli-engine@0.6.3 is published.
• Release Composer CLI with engine peer/dev/internal pins at 0.6.3.
• Release ORM toolchain with engine peer/build pins at 0.6.3.
• Update both CLI consumer manifests to the compatible released families; align their dev dist-tags too.
• Remove the two 0.6.2 → 0.6.3 entries in packages/cli/scripts/conformance.ts; verify release and dev conformance.
• Verify fresh Bun orm init and standalone contract emit against the published CLI.

The exceptions are development-channel-only. They allow the temporary two-engine install so the engine can publish first; they do not make that mixed tree a verified release. Release-channel conformance must remain failing until the families align.