feat(life): add Life Post detail page and endpoint

Implement GET /api/life-posts/:id with moderation and visibility rules
Add /life/:id route and LifePostDetail view
Update feeds and user profiles to link to the new detail page

frontend/src/services/api.ts

@@ -1030,6 +1030,7 @@ export const api = {
         sort: params.sort
       })}`
     ),
+  lifePost: (id: string | number) => getJson<LifePost>(`/api/life-posts/${id}`),
   createLifePost: (payload: LifePostPayload) => sendJson<LifePost>('/api/life-posts', 'POST', payload),
   updateLifePost: (id: string | number, payload: LifePostPayload) =>
     sendJson<LifePost>(`/api/life-posts/${id}`, 'PUT', payload),