feat(finance-permissions): implement permission checks for finance data editing

- Added permission checks for editing finance data, including fixed costs and rate cards.
- Introduced utility functions to determine user permissions based on roles (admin, project manager).
- Updated finance and rate card components to conditionally render UI elements based on user permissions.
- Displayed alerts for users with limited access to inform them of their editing capabilities.

worklenz-frontend/src/utils/finance-permissions.ts

@@ -0,0 +1,58 @@
+import { ILocalSession } from '@/types/auth/local-session.types';
+import { IProjectViewModel } from '@/types/project/projectViewModel.types';
+
+/**
+ * Checks if the current user has permission to edit finance data
+ * Only users with project admin, admin or owner roles should be able to:
+ * - Change fixed cost values
+ * - Add members to rate cards
+ * - Change rate per hour values
+ */
+export const hasFinanceEditPermission = (
+  currentSession: ILocalSession | null,
+  currentProject?: IProjectViewModel | null
+): boolean => {
+  if (!currentSession) return false;
+
+  // Team owner or admin always have permission
+  if (currentSession.owner || currentSession.is_admin) {
+    return true;
+  }
+
+  // Project manager has permission
+  if (currentProject?.project_manager?.id === currentSession.team_member_id) {
+    return true;
+  }
+
+  return false;
+};
+
+/**
+ * Checks if the current user can edit fixed costs
+ */
+export const canEditFixedCost = (
+  currentSession: ILocalSession | null,
+  currentProject?: IProjectViewModel | null
+): boolean => {
+  return hasFinanceEditPermission(currentSession, currentProject);
+};
+
+/**
+ * Checks if the current user can edit rate card data
+ */
+export const canEditRateCard = (
+  currentSession: ILocalSession | null,
+  currentProject?: IProjectViewModel | null
+): boolean => {
+  return hasFinanceEditPermission(currentSession, currentProject);
+};
+
+/**
+ * Checks if the current user can add members to rate cards
+ */
+export const canAddMembersToRateCard = (
+  currentSession: ILocalSession | null,
+  currentProject?: IProjectViewModel | null
+): boolean => {
+  return hasFinanceEditPermission(currentSession, currentProject);
+};