v0.5.0

Upgrading from v0.4.1 requires stopping the whole fleet first.

Highlights:

- Support for Containers and the Cloudflare Sandbox SDK.
- Support for worker_loaders in wrangler.json. Loaded Workers can receive
  service bindings and use a custom outbound fetch handler.
- Service bindings now support fetch() on named entrypoints across Workers.
- RPC support for default service bindings and nested properties.
  AbortSignal can pass through RPC calls on the same node.
- Choose how long to keep completed Workflow runs, or delete them manually.
- Support for .dev.vars in celld dev, with automatic reloads.
- Support for WASM files in prebuilt deployments.
- Lower memory use per cell and faster KV prefix listings.
- Fixes for nested transactions, facet rollback, and unfinished SQL writes.
- More reliable alarm delivery and background work after a response.
- Database recovery fixes, with lower memory use during recovery and
  compaction.
- Internal host functions are no longer exposed to application code.
- Configure telemetry with CELLD_OTEL: 1 for the bucket, or an OTLP
  collector URL.

Issues fixed:

- #177: Pass service bindings to loaded Workers.
- #192: Isolate host state between loaded Workers.
- #193: Recover cells after their owner freezes.
- #194, #195, #196, #197: Fix Base64 and argument handling.
- #198, #199: Fix database compaction and restore failures.
- #200: Resume async work when another request wakes it.
- #201: Recognize minified imports for Node.js builtins.
- #203: Fix duplicate WebSocket Close frames.

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
Co-authored-by: Nathan Whitaker <nathan@deno.com>
Co-authored-by: Yusuke Tanaka <yusuktan@maguro.dev>
Co-authored-by: Andrew Joslin <andrew@joinboja.com>