Native engine: support KV, D1, R2, Queues, Workflows, service bindings and assets #116

docs/native-engine.md lists these as "Not yet. The engine refuses a config that declares them."

A Wrangler project that uses any of them cannot run on the native engine at all, which limits it to Durable Objects-only apps.

Do

• Decide scope per binding. KV, R2 and Queues are the likely first targets; Workflows and assets are larger.
• Implement behind the existing shim pattern in packages/cli/src/native/ (workers-shim.js, email-shim.js).
• Keep the refusal for anything not implemented, so a config never silently half-works.
• Add conformance cases for each binding that lands.

Done when

The supported bindings are listed in docs/native-engine.md and docs/compatibility.md, with conformance coverage, and unsupported ones still fail loudly.