New setting write_thread_idle_timeout_ms (default 30000, 0 disables).
A database's write thread now waits on queue.get(timeout=...) and, when
it times out, takes _write_thread_lock, re-checks that the queue is
empty, deregisters itself and closes its write connection. Producers
enqueue and check/start the thread under the same lock, so a task can
never be left in the queue with no thread to run it.
Also: close() refuses new tasks under the lock and joins retiring
threads; a failed connect is retried by the next write once the queue
drains; memory databases never idle out; a thread that dies from a
BaseException deregisters (and restarts if tasks are waiting); the
thread is registered only after start() succeeds.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EwkLo2rJWidpkDVT3HkvNv
This change updates the `-s/--setting` option to `datasette serve` to allow it to be used to set arbitrarily complex nested settings in a way that is compatible with the new `-c datasette.yml` work happening in:
- #2143
It will enable things like this:
```
datasette data.db --setting plugins.datasette-ripgrep.path "/home/simon/code"
```
For the moment though it just affects [settings](https://docs.datasette.io/en/1.0a4/settings.html) - so you can do this:
```
datasette data.db --setting settings.sql_time_limit_ms 3500
```
I've also implemented a backwards compatibility mechanism, so if you use it this way (the old way):
```
datasette data.db --setting sql_time_limit_ms 3500
```
It will notice that the setting you passed is one of Datasette's core settings, and will treat that as if you said `settings.sql_time_limit_ms` instead.
