Add Verifik RETHUS integration: backend module, settings auth flow, admin query button

- verifik.service.ts: email OTP auth, token storage/refresh, RETHUS query by professional
- verifik.controller.ts: send-otp, confirm, refresh, rethus/professional/:id endpoints
- settings/page.tsx: Verifik connection section (email→OTP→token)
- professionals/[id]/page.tsx: Consultar RETHUS button with inline result display

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/src/verifik/verifik.controller.ts

@@ -0,0 +1,43 @@
+import { Controller, Post, Get, Body, Param, Query, UseGuards } from '@nestjs/common';
+import { ApiTags, ApiBearerAuth } from '@nestjs/swagger';
+import { VerifikService } from './verifik.service';
+import { JwtAuthGuard } from '../auth/jwt-auth.guard';
+
+@ApiTags('Verifik')
+@Controller('verifik')
+@UseGuards(JwtAuthGuard)
+@ApiBearerAuth()
+export class VerifikController {
+  constructor(private verifik: VerifikService) {}
+
+  @Get('status')
+  status() { return this.verifik.getStatus(); }
+
+  @Post('send-otp')
+  sendOtp(@Body() body: { email: string }) {
+    return this.verifik.sendOtp(body.email);
+  }
+
+  @Post('confirm')
+  confirm(@Body() body: { email: string; otp: string }) {
+    return this.verifik.confirmOtp(body.email, body.otp);
+  }
+
+  @Post('refresh')
+  refresh() { return this.verifik.refreshToken(); }
+
+  // Query by professional ID — looks up cedula from DB
+  @Get('rethus/professional/:id')
+  rethusByProfessional(@Param('id') id: string) {
+    return this.verifik.queryRethusByProfessional(id);
+  }
+
+  // Direct query by document
+  @Get('rethus')
+  rethus(
+    @Query('documentType') documentType: string,
+    @Query('documentNumber') documentNumber: string,
+  ) {
+    return this.verifik.queryRethus(documentType, documentNumber);
+  }
+}