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/dist/otp/otp-gate.guard.d.ts

@@ -0,0 +1,7 @@
+import { CanActivate, ExecutionContext } from '@nestjs/common';
+import { OtpService } from './otp.service';
+export declare class OtpGateGuard implements CanActivate {
+    private otpService;
+    constructor(otpService: OtpService);
+    canActivate(context: ExecutionContext): Promise<boolean>;
+}