feat: fold traefik into the service widget type, remove the dedicated one

Traefik gets the same treatment as the other six services now instead
of a bespoke widget type: docker health merged with a single "Routes"
stat, via the same internal container-to-container API call
(http://traefik:8080/api/http/routers) it already used. No auth
needed, same as before.

Deleted lib/collectors/traefik.ts, lib/types/traefik-result.ts, and
components/widgets/traefik/ entirely - the generic service Widget.tsx
and ServiceWidgetResult shape cover it with zero new component code.

lib/types/traefik-result.ts

@@ -1,19 +0,0 @@
-export interface TraefikRouterInfo {
-  name: string;
-  rule: string;
-  service: string;
-  status: string;
-  tls: boolean;
-  entryPoints: string[];
-}
-
-export interface TraefikEntrypointInfo {
-  name: string;
-  address: string;
-}
-
-export interface TraefikResult {
-  routers: TraefikRouterInfo[];
-  entrypoints: TraefikEntrypointInfo[];
-  middlewaresCount: number;
-}

lib/types/widget-result.ts

@@ -1,6 +1,5 @@
 import type { SystemResult } from "./system-result";
 import type { HttpCheckResult } from "./http-result";
-import type { TraefikResult } from "./traefik-result";
 import type { ServiceWidgetResult } from "./service-result";
 
 export interface DockerContainerResult {
@@ -20,6 +19,5 @@ export type WidgetResult =
   | { type: "database"; data: DockerContainerResult }
   | { type: "system"; data: SystemResult }
   | { type: "http"; data: HttpCheckResult }
-  | { type: "traefik"; data: TraefikResult }
   | { type: "service"; data: ServiceWidgetResult }
   | { type: "error"; message: string };