Add ignore-self toggle to Jail Detail page

Implements the missing UI control for POST /api/jails/{name}/ignoreself:
- Add jailIgnoreSelf endpoint constant to endpoints.ts
- Add toggleIgnoreSelf(name, on) API function to jails.ts
- Expose toggleIgnoreSelf action from useJailDetail hook
- Replace read-only 'ignore self' badge with a Fluent Switch in
  IgnoreListSection to allow enabling/disabling the flag per jail
- Add 5 vitest tests for checked/unchecked state and toggle behaviour

frontend/src/api/endpoints.ts

@@ -45,6 +45,7 @@ export const ENDPOINTS = {
   jailReload: (name: string): string => `/jails/${encodeURIComponent(name)}/reload`,
   jailsReloadAll: "/jails/reload-all",
   jailIgnoreIp: (name: string): string => `/jails/${encodeURIComponent(name)}/ignoreip`,
+  jailIgnoreSelf: (name: string): string => `/jails/${encodeURIComponent(name)}/ignoreself`,
 
   // -------------------------------------------------------------------------
   // Bans