Bump the core baseline to 4.1.0-RC.5 and delete the alert-side copies in
the spi package. The qbit now registers its sink in core's
AlertsInstanceMetaData, so core QAlerts.raise/resolve/heartbeat from any
host qbit reaches it. The alertsQBitStandIn name is gone.
The notification types (NotificationSignal and friends) and
AlertsRuntime.sink().notify stay, binary compatible, for the released
qbit-easypost-tracking. They are tagged
STAND-IN(core=QRun-IO/qqq#1125, removeBy=4.1.0-RC.6).
StandardWebhookSigner delegates to core WebhookSigner. The wire format is
unchanged. Legacy secrets shorter than core's 16-byte minimum are
zero-padded, which gives an identical HMAC-SHA256.
Refs #15 (architecture review QRun-IO/qqq#1150, F3 and F11).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>