feat: remove OTP gate from transactions, fix categories auth, add implementation plan

- Remove OtpGateGuard from transactions controller (OTP verified at login)
- Fix categories controller to use authenticated user instead of TEMP_USER_ID
- Add comprehensive implementation plan document
- Update .env.example with WEB_APP_URL
- Prepare for admin dashboard development

apps/api/prisma/migrations/20251010054217_add_custom_auth_and_otp/migration.sql

@@ -0,0 +1,37 @@
+/*
+  Warnings:
+
+  - Made the column `email` on table `User` required. This step will fail if there are existing NULL values in that column.
+
+*/
+-- AlterTable
+ALTER TABLE "public"."User" ADD COLUMN     "emailVerified" BOOLEAN NOT NULL DEFAULT false,
+ADD COLUMN     "otpEmailEnabled" BOOLEAN NOT NULL DEFAULT false,
+ADD COLUMN     "otpTotpEnabled" BOOLEAN NOT NULL DEFAULT false,
+ADD COLUMN     "otpTotpSecret" TEXT,
+ADD COLUMN     "passwordHash" TEXT,
+ALTER COLUMN "email" SET NOT NULL;
+
+-- AlterTable
+ALTER TABLE "public"."Wallet" ADD COLUMN     "initialAmount" DECIMAL(18,2),
+ADD COLUMN     "pricePerUnit" DECIMAL(18,2);
+
+-- CreateTable
+CREATE TABLE "public"."Category" (
+    "id" TEXT NOT NULL,
+    "userId" TEXT NOT NULL,
+    "name" TEXT NOT NULL,
+    "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMP(3) NOT NULL,
+
+    CONSTRAINT "Category_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "Category_userId_idx" ON "public"."Category"("userId");
+
+-- CreateIndex
+CREATE UNIQUE INDEX "Category_userId_name_key" ON "public"."Category"("userId", "name");
+
+-- AddForeignKey
+ALTER TABLE "public"."Category" ADD CONSTRAINT "Category_userId_fkey" FOREIGN KEY ("userId") REFERENCES "public"."User"("id") ON DELETE RESTRICT ON UPDATE CASCADE;

apps/api/prisma/migrations/20251010132022_add_phone_and_whatsapp_otp/migration.sql

@@ -0,0 +1,12 @@
+/*
+  Warnings:
+
+  - A unique constraint covering the columns `[phone]` on the table `User` will be added. If there are existing duplicate values, this will fail.
+
+*/
+-- AlterTable
+ALTER TABLE "public"."User" ADD COLUMN     "otpWhatsappEnabled" BOOLEAN NOT NULL DEFAULT false,
+ADD COLUMN     "phone" TEXT;
+
+-- CreateIndex
+CREATE UNIQUE INDEX "User_phone_key" ON "public"."User"("phone");