v0.6.2

Upgrading from v0.6.1 can use a rolling update.

- A Durable Object `stub.fetch()` that a peer forwards now rejects when the handler fails on the owner, as it does locally, and the handler does not run again.
- A Worker that returns a WebSocket response to a request without `Upgrade: websocket` now fails with a `TypeError` and a 500.
- `celld dev` accepts `export NAME=value` lines and multi-line quoted values in `.env` files, and skips an entry that cannot be a binding with a warning.
- Epoch GC (`CELLD_LTX_RETENTION_SECS`) also runs on nodes with bucket durability.
- LTX capture recovers a torn WAL header when a database opens, so capture no longer skips commits after a crash.
- A failed or abandoned eviction no longer stops compaction for the rest of a cell's activation.

Issues fixed:

- #243: `celld dev` reads `.env` and `.env.local` when there is no `.dev.vars`, as `wrangler dev` does.
- #245: A fleet with one follower recruits a second one when a peer becomes available.
- #246: Follower disk use stays bounded after a snapshot eviction or a deleted facet.
- #247: `self` is defined in Worker, Durable Object, and Worker Loader isolates.
- #248: `getDurableObjectClass()` accepts a plain class that extends no runtime base.
- #252: WebSockets work in Durable Object facets, including outbound sockets that a facet opens.
- #255: A deploy no longer deadlocks a Durable Object handler.
- #257: A fetch to a loaded Worker honors the caller's `AbortSignal`, including `AbortSignal.timeout()`.

Co-authored-by: Ryan Dahl <ry@tinyclouds.org>
Co-authored-by: Yusuke "Taka" Tanaka <yusuktan@maguro.dev>
Co-authored-by: Josh Collinsworth <joshuajcollinsworth@gmail.com>
Co-authored-by: Bert Belder <bertbelder@gmail.com>