feat(org): panel-based access system replacing roles (procurement/inventory)

- new tables user_panels (panel: procurement/inventory/pm + level full/limited)
  and user_project_members (M:N membership, separate from pm responsibility)
- UserContext carries panels + member_project_ids; /users/me and the users
  list include them
- admin endpoints: PUT /users/{id}/panels, PUT /users/{id}/panel-projects
- inventory scope: panel inventory 'full' -> manager scope (all projects, NO
  stock change); 'limited' -> supervisor scope (own memberships, stock change
  allowed); legacy roles kept as migration fallback; admin untouched
- procurement writes: _procurement_writer is now panel-aware (admin, legacy
  procurement_manager, or procurement 'full') across all 18 write routers;
  quote CREATE additionally allows 'limited' users restricted to their member
  projects (validated server-side)
- frontend: panel-aware HomeRoute (inventory -> warehouse panel, procurement
  limited -> minimal RequesterHome), wizard project options restricted for
  limited users, change-inventory button/route gated to inventory 'limited',
  organization panel gains the panels & access-levels management section

frontend/src/lib/api.ts

@@ -1562,6 +1562,10 @@ export interface UserRow {
   phone: string | null;
   role: "pm" | "procurement_manager" | "admin" | "supervisor" | null;
   role_label: string | null;
+  // لایه پنل‌ها (جایگزین نقش‌ها): {'procurement': 'full'|'limited', ...}
+  panels?: Record<string, string>;
+  // عضویت M:N پروژه‌ای — محدوده داده سطح limited
+  member_project_ids?: string[];
   project_id: string | null;
   project_name: string | null;
   // 1:N — every project this PM manages (oldest first).
@@ -1657,6 +1661,11 @@ export const apiV26 = {
     }): Promise<UserRow> => postData<UserRow>("/users", body),
     updateRole: async (id: string, role: "pm" | "procurement_manager" | "admin" | "supervisor" | null): Promise<UserRow> =>
       patchData<UserRow>(`/users/${id}`, { role }),
+    // لایه پنل‌ها — تخصیص پنل + سطح دسترسی و عضویت پروژه‌ای (فقط ادمین)
+    setPanels: async (id: string, panels: Record<string, string>): Promise<UserRow> =>
+      patchData<UserRow>(`/users/${id}/panels`, { panels }),
+    setPanelProjects: async (id: string, project_ids: string[]): Promise<UserRow> =>
+      patchData<UserRow>(`/users/${id}/panel-projects`, { project_ids }),
     assignProject: async (id: string, projectId: string | null): Promise<UserRow> =>
       postData<UserRow>(`/users/${id}/project`, { project_id: projectId }),
     // همگام‌سازی هویت‌ها از Casdoor (ادمین/مدیر تدارکات) — نقش‌ها دست‌نخورده می‌مانند