feat: complete maintenance tracking backend

Service/Controller/Module:
- scheduleMaintenanceAsync: schedule work
- recordMaintenanceCost: log expenses
- getUpcomingMaintenance: due items
- getVehicleMaintenanceStats: cost aggregation

Endpoints:
- POST /maintenance/schedules
- POST /maintenance/costs
- PATCH /maintenance/schedules/:id
- GET /maintenance/upcoming/:vehicleId
- GET /maintenance/history/:vehicleId
- GET /maintenance/stats/:vehicleId

Migration: idempotent maintenance tables creation

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

apps/edr-freight-api/src/migrations/1850000000000-CreateMaintenanceTables.ts

@@ -0,0 +1,82 @@
+import { MigrationInterface, QueryRunner } from 'typeorm';
+
+export class CreateMaintenanceTables1850000000000 implements MigrationInterface {
+  public async up(queryRunner: QueryRunner): Promise<void> {
+    // Create maintenance_schedules table
+    const scheduleTableExists = await queryRunner.query(`
+      SELECT EXISTS(
+        SELECT 1 FROM information_schema.tables
+        WHERE table_schema = 'freight' AND table_name = 'maintenance_schedules'
+      )
+    `);
+
+    if (!scheduleTableExists[0].exists) {
+      await queryRunner.query(`
+        CREATE TABLE "freight"."maintenance_schedules" (
+          "id" uuid NOT NULL DEFAULT gen_random_uuid(),
+          "vehicle_id" uuid NOT NULL,
+          "maintenance_type" varchar NOT NULL,
+          "description" varchar NOT NULL,
+          "scheduled_date" timestamptz NOT NULL,
+          "completed_date" timestamptz,
+          "estimated_cost" numeric(14,2),
+          "actual_cost" numeric(14,2),
+          "status" varchar NOT NULL DEFAULT 'SCHEDULED',
+          "odometer_reading" numeric,
+          "service_provider" varchar,
+          "notes" text,
+          "next_due_km" numeric,
+          "next_due_date" timestamptz,
+          "created_at" timestamptz NOT NULL DEFAULT now(),
+          "updated_at" timestamptz NOT NULL DEFAULT now(),
+          "deleted_at" timestamptz,
+          PRIMARY KEY ("id")
+        )
+      `);
+
+      await queryRunner.query(
+        `CREATE INDEX "idx_maintenance_schedules_vehicle_date" ON "freight"."maintenance_schedules" ("vehicle_id", "scheduled_date")`
+      );
+    }
+
+    // Create maintenance_costs table
+    const costsTableExists = await queryRunner.query(`
+      SELECT EXISTS(
+        SELECT 1 FROM information_schema.tables
+        WHERE table_schema = 'freight' AND table_name = 'maintenance_costs'
+      )
+    `);
+
+    if (!costsTableExists[0].exists) {
+      await queryRunner.query(`
+        CREATE TABLE "freight"."maintenance_costs" (
+          "id" uuid NOT NULL DEFAULT gen_random_uuid(),
+          "vehicle_id" uuid NOT NULL,
+          "maintenance_schedule_id" uuid,
+          "incurred_date" timestamptz NOT NULL,
+          "cost_amount" numeric(14,2) NOT NULL,
+          "cost_type" varchar NOT NULL,
+          "description" varchar NOT NULL,
+          "service_provider" varchar,
+          "invoice_number" varchar,
+          "notes" text,
+          "created_at" timestamptz NOT NULL DEFAULT now(),
+          "updated_at" timestamptz NOT NULL DEFAULT now(),
+          "deleted_at" timestamptz,
+          PRIMARY KEY ("id"),
+          CONSTRAINT "fk_maintenance_schedule" FOREIGN KEY ("maintenance_schedule_id")
+            REFERENCES "freight"."maintenance_schedules" ("id") ON DELETE SET NULL
+        )
+      `);
+
+      await queryRunner.query(
+        `CREATE INDEX "idx_maintenance_costs_vehicle_date" ON "freight"."maintenance_costs" ("vehicle_id", "incurred_date")`
+      );
+    }
+  }
+
+  public async down(queryRunner: QueryRunner): Promise<void> {
+    await queryRunner.query(`DROP TABLE IF EXISTS "freight"."maintenance_costs"`);
+    await queryRunner.query(`DROP TABLE IF EXISTS "freight"."maintenance_schedules"`);
+  }
+}