v0.9.1

• Added: serialise gathers — one per host, capped fleet-wide — to spare upstreams
• Fixed: atomic_open temp name is unique per call, not just per pid
• Added: reject a D1 database name in place of the Database ID, with guidance
• Added: stateless HTTP mode (on by default) with a knob to disable it
• Added: configurable Host/Origin allow-list for the HTTP transport
• Fixed: upstream auth failures now give an actionable error, not a traceback
• Fixed: a second client now sees a running gather instead of clobbering it