feat: finish the host-metrics plugin, move host status into core (B16)

drizzle/sqlite/0040_rich_zuras.sql

@@ -0,0 +1,9 @@
+-- host_metrics_preferences, host_health_checks, host_health_history and
+-- host_metrics_history moved to the host-metrics plugin, which adopts them by
+-- rename in its own first migration. That runs after this one, so a real
+-- DROP TABLE here would delete every row first.
+SELECT 1;--> statement-breakpoint
+-- Status checks are core: the per-host switch and interval, copied out of
+-- stats_config at boot by host-status-config-migration.ts.
+ALTER TABLE `ssh_data` ADD `status_check_enabled` integer DEFAULT true NOT NULL;--> statement-breakpoint
+ALTER TABLE `ssh_data` ADD `status_check_interval` integer;