feat: add public read-only sharing for computers

Adds the ability for an owner to share a computer build via a public,
unauthenticated link, inspired by a feature request from the original
pcbuilder repo (no such feature actually existed there — implemented
from scratch here).

- New columns on computers: share_token (unique, nullable), share_enabled,
  share_show_sell_price, share_show_cost
- computer_share_service.ts: generates a non-guessable share token
  (crypto.randomBytes, base64url), enables/disables sharing, and supports
  rotating the token to invalidate previously distributed links
- ComputerShareController (authenticated, owner-scoped like the rest of
  the app): PUT /computers/:id/share to update settings, POST
  /computers/:id/share/rotate to rotate the token
- PublicComputerController + GET /share/:token (outside any auth/guest
  group, reachable anonymously): resolves only computers with
  share_enabled = true, 404 otherwise
- ComputerPublicTransformer: dedicated read-only projection that never
  leaks userId, and only includes sellPrice/cost when the owner opted in
  via share_show_sell_price / share_show_cost — everything else (title,
  scores, state, components, pictures) is always visible on a shared link
- ComputerShareModal.vue: owner-facing UI (toggle sharing, choose which
  prices to expose, copy the public link, revoke/rotate it) wired into
  computers/show.vue via a new 'Share' button
- share/show.vue: public page rendered with EmptyLayout (no authenticated
  header/sidebar)
- Boolean columns use a  cast since MySQL returns tinyint(1),
  not native booleans, through Lucid
- 6 new functional tests covering: enabling sharing, price visibility
  toggles, disabling sharing revokes the link, cross-user protection on
  the share settings endpoint (404), token rotation invalidating the old
  link, and anonymous access to a shared computer

.adonisjs/server/controllers.ts

@@ -5,7 +5,9 @@
 
 export const controllers = {
   Components: () => import('#controllers/components_controller'),
+  ComputerShare: () => import('#controllers/computer_share_controller'),
   Computers: () => import('#controllers/computers_controller'),
   NewAccount: () => import('#controllers/new_account_controller'),
+  PublicComputer: () => import('#controllers/public_computer_controller'),
   Session: () => import('#controllers/session_controller'),
 }

.adonisjs/server/pages.d.ts

@@ -26,11 +26,13 @@ declare module '@adonisjs/inertia/types' {
     'layout/emptyLayout': ExtractProps<(typeof import('../../inertia/pages/layout/emptyLayout.vue'))['default']>
     'layout/header': ExtractProps<(typeof import('../../inertia/pages/layout/header.vue'))['default']>
     'layout/sidebar': ExtractProps<(typeof import('../../inertia/pages/layout/sidebar.vue'))['default']>
+    'share/show': ExtractProps<(typeof import('../../inertia/pages/share/show.vue'))['default']>
     'widgets/AuthErrorAlert': ExtractProps<(typeof import('../../inertia/pages/widgets/AuthErrorAlert.vue'))['default']>
     'widgets/ComponentEditor': ExtractProps<(typeof import('../../inertia/pages/widgets/ComponentEditor.vue'))['default']>
     'widgets/ComponentsViewer': ExtractProps<(typeof import('../../inertia/pages/widgets/ComponentsViewer.vue'))['default']>
     'widgets/ComputerCard': ExtractProps<(typeof import('../../inertia/pages/widgets/ComputerCard.vue'))['default']>
     'widgets/ComputerComponentsTable': ExtractProps<(typeof import('../../inertia/pages/widgets/ComputerComponentsTable.vue'))['default']>
+    'widgets/ComputerShareModal': ExtractProps<(typeof import('../../inertia/pages/widgets/ComputerShareModal.vue'))['default']>
     'widgets/ComputersViewer': ExtractProps<(typeof import('../../inertia/pages/widgets/ComputersViewer.vue'))['default']>
     'widgets/CustomSelect': ExtractProps<(typeof import('../../inertia/pages/widgets/CustomSelect.vue'))['default']>
     'widgets/DeleteConfirmationModal': ExtractProps<(typeof import('../../inertia/pages/widgets/DeleteConfirmationModal.vue'))['default']>

.adonisjs/server/routes.d.ts

@@ -17,6 +17,9 @@ export type ScannedRoutes = {
     'computers.edit': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
     'computers.update': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
     'computers.destroy': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
+    'computers.share.update': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
+    'computers.share.rotate': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
+    'share.show': { paramsTuple: [ParamValue]; params: {'token': ParamValue} }
     'components.index': { paramsTuple?: []; params?: {} }
     'components.create': { paramsTuple?: []; params?: {} }
     'components.store': { paramsTuple?: []; params?: {} }
@@ -33,6 +36,7 @@ export type ScannedRoutes = {
     'computers.create': { paramsTuple?: []; params?: {} }
     'computers.show': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
     'computers.edit': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
+    'share.show': { paramsTuple: [ParamValue]; params: {'token': ParamValue} }
     'components.index': { paramsTuple?: []; params?: {} }
     'components.create': { paramsTuple?: []; params?: {} }
     'components.show': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
@@ -46,6 +50,7 @@ export type ScannedRoutes = {
     'computers.create': { paramsTuple?: []; params?: {} }
     'computers.show': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
     'computers.edit': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
+    'share.show': { paramsTuple: [ParamValue]; params: {'token': ParamValue} }
     'components.index': { paramsTuple?: []; params?: {} }
     'components.create': { paramsTuple?: []; params?: {} }
     'components.show': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
@@ -56,10 +61,12 @@ export type ScannedRoutes = {
     'session.store': { paramsTuple?: []; params?: {} }
     'session.destroy': { paramsTuple?: []; params?: {} }
     'computers.store': { paramsTuple?: []; params?: {} }
+    'computers.share.rotate': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
     'components.store': { paramsTuple?: []; params?: {} }
   }
   PUT: {
     'computers.update': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
+    'computers.share.update': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
     'components.update': { paramsTuple: [ParamValue]; params: {'id': ParamValue} }
   }
   DELETE: {