revert: restore production to the state before 730d0bd (PM/RBAC work moved to 'pm')

Their three commits (730d0bd, 5a9b543, 387edfb) reached production by push and
auto-deployed. 387edfb expects a users.username column that the live database does
not have, so POST /api/v1/auth/login was returning HTTP 500. Their schema changes
never applied either (projects still has only id, name, description, start_date,
pm_user_id, created_at), so nothing depends on the reverted code.

This commit sets the tree back to exactly a02b3ea — verified with git diff against
it — while keeping history linear: the work itself is preserved on 'pm' at 387edfb.

frontend/src/store/index.ts

@@ -41,7 +41,6 @@ interface AppStore {
   deleteSupplier: (id: string) => void;
   addMaterial: (m: Material) => void;
   addProject: (p: Project) => void;
-  deleteProject: (id: string) => void;
   setStandardConversion: (sc: StandardConversion) => void;
   deleteStandardConversion: (id: string) => void;
 
@@ -86,7 +85,6 @@ export const useAppStore = create<AppStore>()((set) => ({
   deleteSupplier: (id) => set((s) => ({ suppliers: s.suppliers.filter((x) => x.id !== id) })),
   addMaterial: (m) => set((s) => ({ materials: [...s.materials, m] })),
   addProject: (p) => set((s) => ({ projects: [...s.projects, p] })),
-  deleteProject: (id) => set((s) => ({ projects: s.projects.filter((p) => p.id !== id) })),
   setStandardConversion: (sc) =>
     set((s) => {
       const idx = s.standardConversions.findIndex((x) => x.id === sc.id);