ADR-013 Phase 4: extract the 11 plugin routes embedded in core.js

core.js still routed plugin-owned pages directly. Extracted all 11 into the
owning plugin's route file + moved their views into plugins/<name>/frontend/:
- computers: reports/pc-relationships, settings/pctypemapping
- printers: reports/toner, settings/printertypes, settings/zabbix (toner/supply
  monitoring)
- machines: settings/machinetypes
- network: settings/networktypes
- warranty: settings/dellwarranty
- slides: settings/slides (its route file gains a default export; it was
  toplevel-only)
- employees: NEW plugin frontend (employees/:sso + settings/employeedirectory) -
  employees had no route file before; its pages lived only in core.js.

core.js now holds only core routes; all 14 bundled plugins are self-contained
under plugins/<name>/frontend/. Verified live: the extracted Machine Types
settings page renders in the settings rail from the machines plugin frontend.
Build + 58 vitest + naming green.

frontend/src/router/routes/core.js

@@ -28,24 +28,6 @@ export default [
     name: 'reports',
     component: () => import('../../views/reports/ReportsIndex.vue')
   },
-  {
-    path: 'reports/pc-relationships',
-    name: 'report-pc-relationships',
-    component: () => import('../../views/reports/PCRelationshipsReport.vue'),
-    meta: { plugin: 'computers' }
-  },
-  {
-    path: 'reports/toner',
-    name: 'toner-report',
-    component: () => import('../../views/reports/TonerReport.vue'),
-    meta: { plugin: 'printers' }
-  },
-  {
-    path: 'employees/:sso',
-    name: 'employee-detail',
-    component: () => import('../../views/employees/EmployeeDetail.vue'),
-    meta: { plugin: 'employees' }
-  },
   // Settings
   {
     path: 'settings',
@@ -107,30 +89,6 @@ export default [
     component: () => import('../../views/settings/SiteSettings.vue'),
     meta: { requiresAuth: true, requiresAdmin: true }
   },
-  {
-    path: 'settings/slides',
-    name: 'slide-manager',
-    component: () => import('../../views/settings/SlideManager.vue'),
-    meta: { requiresAuth: true, requiresAdmin: true, plugin: 'slides' }
-  },
-  {
-    path: 'settings/machinetypes',
-    name: 'machinetypes',
-    component: () => import('../../views/settings/MachineTypesList.vue'),
-    meta: { requiresAuth: true, requiresAdmin: true }
-  },
-  {
-    path: 'settings/networktypes',
-    name: 'network-types',
-    component: () => import('../../views/settings/NetworkTypesList.vue'),
-    meta: { requiresAuth: true, requiresAdmin: true }
-  },
-  {
-    path: 'settings/printertypes',
-    name: 'printer-types',
-    component: () => import('../../views/settings/PrinterTypesList.vue'),
-    meta: { requiresAuth: true, requiresAdmin: true }
-  },
   {
     path: 'settings/relationshiptypes',
     name: 'relationship-types',
@@ -155,12 +113,6 @@ export default [
     component: () => import('../../views/settings/CustomFieldsList.vue'),
     meta: { requiresAuth: true, requiresAdmin: true }
   },
-  {
-    path: 'settings/employeedirectory',
-    name: 'employee-directory',
-    component: () => import('../../views/settings/EmployeeDirectory.vue'),
-    meta: { requiresAuth: true, requiresAdmin: true }
-  },
   // The old monolithic System Settings tab page is split into one routed page
   // per section (below). This redirect keeps old bookmarks working: bare
   // /settings/system and every /settings/system?tab=<key> land on the right page.
@@ -192,24 +144,6 @@ export default [
     component: () => import('../../views/settings/ServiceNowSettings.vue'),
     meta: { requiresAuth: true, requiresAdmin: true }
   },
-  {
-    path: 'settings/zabbix',
-    name: 'zabbix-settings',
-    component: () => import('../../views/settings/ZabbixSettings.vue'),
-    meta: { requiresAuth: true, requiresAdmin: true }
-  },
-  {
-    path: 'settings/dellwarranty',
-    name: 'dell-warranty-settings',
-    component: () => import('../../views/settings/DellWarrantySettings.vue'),
-    meta: { requiresAuth: true, requiresAdmin: true }
-  },
-  {
-    path: 'settings/pctypemapping',
-    name: 'pctype-mapping-settings',
-    component: () => import('../../views/settings/PCTypeMappingSettings.vue'),
-    meta: { requiresAuth: true, requiresAdmin: true }
-  },
   {
     path: 'settings/branding',
     name: 'branding-settings',