chore: add loan model prisma migration (#56)

Author: AnoukRImola

apps/core/prisma/migrations/20260311220446_add_loan_model/migration.sql

@@ -0,0 +1,22 @@
+-- CreateEnum
+CREATE TYPE "LoanStatus" AS ENUM ('PENDING', 'DISBURSED', 'REPAID', 'DEFAULTED');
+
+-- CreateTable
+CREATE TABLE "loans" (
+    "id" TEXT NOT NULL,
+    "campaignId" TEXT NOT NULL,
+    "description" TEXT NOT NULL,
+    "amount" DECIMAL(65,30) NOT NULL,
+    "receiver" TEXT NOT NULL,
+    "milestoneIndex" INTEGER,
+    "status" "LoanStatus" NOT NULL DEFAULT 'PENDING',
+    "disbursedAt" TIMESTAMP(3),
+    "repaidAt" TIMESTAMP(3),
+    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMP(3) NOT NULL,
+
+    CONSTRAINT "loans_pkey" PRIMARY KEY ("id")
+);
+
+-- AddForeignKey
+ALTER TABLE "loans" ADD CONSTRAINT "loans_campaignId_fkey" FOREIGN KEY ("campaignId") REFERENCES "campaigns"("id") ON DELETE RESTRICT ON UPDATE CASCADE;