[ci skip] add widgets for qbittorrent, navidrome, nextcloud, freshrss, linkwarden, uptime-kuma

Add API credentials to SOPS and wire homepage_credentials through
stacks. Re-add Uptime Kuma widget with new "infra" status page slug.

stacks/platform/modules/uptime-kuma/main.tf

@@ -152,6 +152,9 @@ module "ingress" {
     "gethomepage.dev/icon" : "uptime-kuma.png"
     "gethomepage.dev/name"         = "Uptime Kuma"
     "gethomepage.dev/pod-selector" = ""
+    "gethomepage.dev/widget.type"  = "uptimekuma"
+    "gethomepage.dev/widget.url"   = "http://uptime-kuma.uptime-kuma.svc.cluster.local:3001"
+    "gethomepage.dev/widget.slug"  = "infra"
   }
   rybbit_site_id = "8fef77b1f7fe"
 }