ctx.plugin (PluginSelfApi) lets a background module control how its own plugin appears in the shell. Today that means the sidebar indicator: a small badge drawn on the plugin’s nav button.
type is "notification" (a dot) or "warning" (an amber triangle). A plugin cannot set the system error badge — that is reserved for a crashed plugin and always takes precedence over a plugin-set indicator.
Lifetime. An indicator persists until you call clearIndicator() (or the app restarts), unless you pass dismissOnOpen: true, in which case the shell clears it automatically the first time the pilot opens your plugin.
When to use it: to draw the pilot’s eye to your plugin when something there needs their attention. For an active interruption, use ctx.notify, ctx.dialog, or ctx.prompt instead.