feat(rates): last-mile rate rules with bulk per-ton-km and container distance bands

- rates: min_km/max_km columns, PER_TON_KM unit, ETB|USD currency for last mile
- extend UQ_rates_pattern with band start; overlap + shape validation
- shared last-mile charge resolver; approve-dialog price estimate endpoint
- delivery-fee invoice prices via rules, falls back to vehicle price/km
- backoffice: last-mile rate form (mode, container type, band, currency)

apps/edr-freight-web/backoffice/src/services/last-mile-requests.service.ts

@@ -37,6 +37,15 @@ export interface LastMileRequestListResponse {
   meta: { total: number; page: number; pageSize: number; totalPages: number };
 }
 
+/** Rule-based estimate for the approve dialog — all nulls when no rule covers the job. */
+export interface LastMilePriceEstimate {
+  estimatedKm: number | null;
+  mode: 'BULK' | 'CONTAINER' | null;
+  currency: string | null;
+  total: number | null;
+  lines: Array<{ description: string; amount: number }>;
+}
+
 const LMR = URL_CONSTANTS.LAST_MILE_REQUESTS;
 
 export const lastMileRequestsService = {
@@ -44,6 +53,7 @@ export const lastMileRequestsService = {
     api.get<LastMileRequestListResponse>(LMR.BASE, { params }),
   getById: (id: string) => api.get<LastMileRequest>(LMR.BY_ID(id)),
   freeTruckCount: () => api.get<{ count: number }>(LMR.FREE_TRUCK_COUNT),
+  priceEstimate: (id: string) => api.get<LastMilePriceEstimate>(LMR.PRICE_ESTIMATE(id)),
   approve: (id: string, advanceAmount: number) =>
     api.post<LastMileRequest>(LMR.APPROVE(id), { advanceAmount }),
   reject: (id: string, reason: string) =>