fix: Response wrapping, error logging, and controller hardening (COA 3)

- HttpExceptionFilter: Log actual error details for non-HttpExceptions (was silently swallowing 500s)
- ServersService: Return null fields instead of 404 for new licenses without servers
- NotificationsController: Wrap config responses as { config } to match frontend expectations
- WebstoreController: Wrap config responses as { config } to match frontend expectations
- ChatController: Replace ParseIntPipe with manual parseInt (400 on missing optional param)
- WipesController: Same ParseIntPipe fix for history limit param

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

backend-nest/src/common/filters/http-exception.filter.ts

@@ -4,14 +4,18 @@ import {
   ArgumentsHost,
   HttpException,
   HttpStatus,
+  Logger,
 } from '@nestjs/common';
 import { Response } from 'express';
 
 @Catch()
 export class HttpExceptionFilter implements ExceptionFilter {
+  private readonly logger = new Logger('ExceptionFilter');
+
   catch(exception: unknown, host: ArgumentsHost) {
     const ctx = host.switchToHttp();
     const response = ctx.getResponse<Response>();
+    const request = ctx.getRequest();
 
     let status = HttpStatus.INTERNAL_SERVER_ERROR;
     let message = 'Internal server error';
@@ -28,6 +32,13 @@ export class HttpExceptionFilter implements ExceptionFilter {
           message = obj.message[0] as string;
         }
       }
+    } else {
+      // Log non-HttpException errors with full details
+      const err = exception instanceof Error ? exception : new Error(String(exception));
+      this.logger.error(
+        `Unhandled exception on ${request.method} ${request.url}: ${err.message}`,
+        err.stack,
+      );
     }
 
     response.status(status).json({ message });

backend-nest/src/modules/chat/chat.controller.ts

@@ -1,4 +1,4 @@
-import { Controller, Get, Put, Param, Body, Query, ParseIntPipe, UseGuards } from '@nestjs/common';
+import { Controller, Get, Put, Param, Body, Query, UseGuards } from '@nestjs/common';
 import { ApiTags, ApiBearerAuth, ApiOperation, ApiQuery } from '@nestjs/swagger';
 import { ChatService } from './chat.service';
 import { FlagMessageDto } from './dto/flag-message.dto';
@@ -21,9 +21,10 @@ export class ChatController {
   @ApiQuery({ name: 'limit', required: false, example: 100 })
   async getMessages(
     @CurrentTenant() licenseId: string,
-    @Query('limit', new ParseIntPipe({ optional: true })) limit?: number,
+    @Query('limit') limit?: string,
   ) {
-    return await this.chatService.getMessages(licenseId, limit || 100);
+    const limitNum = limit ? parseInt(limit, 10) : 100;
+    return await this.chatService.getMessages(licenseId, limitNum);
   }
 
   @Put(':id/flag')

backend-nest/src/modules/notifications/notifications.controller.ts

@@ -27,7 +27,8 @@ export class NotificationsController {
     description: 'Notification config retrieved successfully',
   })
   async getConfig(@CurrentTenant() licenseId: string) {
-    return await this.notificationsService.getConfig(licenseId);
+    const config = await this.notificationsService.getConfig(licenseId);
+    return { config };
   }
 
   @Put('config')
@@ -43,6 +44,7 @@ export class NotificationsController {
     @CurrentTenant() licenseId: string,
     @Body() dto: UpdateConfigDto,
   ) {
-    return await this.notificationsService.updateConfig(licenseId, dto);
+    const config = await this.notificationsService.updateConfig(licenseId, dto);
+    return { config };
   }
 }

backend-nest/src/modules/servers/servers.service.ts

@@ -17,7 +17,8 @@ export class ServersService {
   ) {}
 
   /**
-   * Get server connection and config for a license
+   * Get server connection and config for a license.
+   * Returns null fields if no server has been set up yet.
    */
   async getServer(licenseId: string) {
     const connection = await this.connectionRepo.findOne({
@@ -28,11 +29,11 @@ export class ServersService {
       where: { license_id: licenseId },
     });
 
-    if (!connection || !config) {
-      throw new NotFoundException('Server not found for this license');
-    }
-
-    return { connection, config };
+    return {
+      connection: connection || null,
+      config: config || null,
+      setup_required: !connection || !config,
+    };
   }
 
   /**

backend-nest/src/modules/webstore/webstore.controller.ts

@@ -18,7 +18,8 @@ export class WebstoreController {
   @ApiBearerAuth()
   @ApiOperation({ summary: 'Get webstore configuration' })
   async getConfig(@CurrentTenant() licenseId: string) {
-    return this.webstoreService.getConfig(licenseId);
+    const config = await this.webstoreService.getConfig(licenseId);
+    return { config };
   }
 
   @Put('webstore/config')
@@ -28,7 +29,8 @@ export class WebstoreController {
     @CurrentTenant() licenseId: string,
     @Body() dto: UpdateStoreConfigDto,
   ) {
-    return this.webstoreService.updateConfig(licenseId, dto);
+    const config = await this.webstoreService.updateConfig(licenseId, dto);
+    return { config };
   }
 
   @Get('webstore/categories')

backend-nest/src/modules/wipes/wipes.controller.ts

@@ -7,7 +7,6 @@ import {
   Body,
   Param,
   Query,
-  ParseIntPipe,
   UseGuards,
 } from '@nestjs/common';
 import { ApiTags, ApiBearerAuth, ApiOperation, ApiQuery } from '@nestjs/swagger';
@@ -81,9 +80,10 @@ export class WipesController {
   @ApiQuery({ name: 'limit', required: false, example: 50 })
   getHistory(
     @CurrentTenant() licenseId: string,
-    @Query('limit', new ParseIntPipe({ optional: true })) limit?: number,
+    @Query('limit') limit?: string,
   ) {
-    return this.wipesService.getHistory(licenseId, limit || 50);
+    const limitNum = limit ? parseInt(limit, 10) : 50;
+    return this.wipesService.getHistory(licenseId, limitNum);
   }
 
   @Post('trigger')