Dendra 0.11.0 — SSE streams and job status on the client

• Server-Sent Events. createClient(url, { streamFormat: "sse" }) streams
  .stream() procedures as SSE instead of NDJSON, for proxies and CDNs that
  buffer NDJSON. The server picks the format from Accept, so no server change
  is needed. Errors still arrive as a typed DendraClientError, and stopping
  the loop still aborts the handler's signal. Idle streams send a : ping
  every 15 s (server option heartbeatMs). A .get() stream also works with a
  plain browser EventSource; close it on the done event.
• Following a job in the browser. useJob(jobId, open) in dendra/react,
  and followJob(open) in core, follow a background job until it succeeds or
  fails, with no polling. A dropped connection reopens after a backoff and picks
  up the current state; NOT_FOUND, UNAUTHORIZED and other coded errors stop
  it and set error.
• Streams through proxies. Stream responses send Cache-Control: no-cache
  and X-Accel-Buffering: no, and toNodeHandler flushes after each chunk so
  Express's compression() doesn't hold them back. The README's new "Deploying
  streams" section covers nginx, Caddy, compression, idle timeouts and
  WebSockets behind a proxy.

Behaviour change: if a stream fails before it starts (for example,
createContext throws), the client now throws the error. Before, the loop
received the error object as an ordinary value.

No upgrade steps are needed.