Add professor share & financial reports UI, expense management page

Adds payout configuration fields (percentage/hourly + per-session
expense allowance) with a live payout preview to the class form,
a new Financial Reports page (per-class and date-range/monthly tabs,
per-session drill-down dialog) with reusable stat cards, and an
Institutional Expenses management page. Registers routes, sidebar
navigation, and permission constants for the new financial_reports
and expenses permissions.

src/api/expenseApi.js

@@ -0,0 +1,10 @@
+// /src/api/expenseApi.js
+import axiosInstance from './axiosInstance';
+
+export const expenseApi = {
+  getAll: (params) => axiosInstance.get('/expenses/admin/get-all', { params }),
+  getOne: (id) => axiosInstance.get(`/expenses/admin/get-one/${id}`),
+  create: (data) => axiosInstance.post('/expenses/admin/create', data),
+  update: (id, data) => axiosInstance.put(`/expenses/admin/update/${id}`, data),
+  delete: (id) => axiosInstance.delete(`/expenses/admin/delete/${id}`)
+};

src/api/financialReportApi.js

@@ -0,0 +1,8 @@
+// /src/api/financialReportApi.js
+import axiosInstance from './axiosInstance';
+
+export const financialReportApi = {
+  getClassReport: (classId) => axiosInstance.get(`/financial-reports/admin/classes/${classId}`),
+  getSessionReport: (sessionId) => axiosInstance.get(`/financial-reports/admin/sessions/${sessionId}`),
+  getRangeReport: (params) => axiosInstance.get('/financial-reports/admin/range', { params })
+};