Relay v0.21.0

Features

• hooks: name the missing events in Settings too
• hooks: repair hook sets left behind by an older Relay

Fixes

• agents: say why the event runtime failed to start
• notifications: keep one live banner per tab instead of stacking
• agents: stop losing hook events under burst
• agents: log the real reason a transport error dropped an event

Other

• cut the module map down to a pointer
• guide: explain that hook sets can fall behind
• attribute only what Relay actually ships
• correct the Cycle 27 outcome and the Settings drift note
• record Cycle 27, rotate cycles 12-13, realign the notification docs
• notifications: cover the delivery filter with a pure policy

Full Changelog: v0.20.0...v0.21.0