fix: address code review issues and cleanup QA reports

Code review fixes:
- Add error logging to LlmProviderAdminController.testProvider catch block
- Use atomic increment operations in TokenBudgetService.updateUsage to prevent race conditions
- Update test expectations for atomic increment pattern

Cleanup:
- Remove obsolete QA automation reports

All 1169 tests passing.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/api/src/llm/llm-provider-admin.controller.ts

@@ -10,6 +10,7 @@ import {
   HttpStatus,
   NotFoundException,
   BadRequestException,
+  Logger,
 } from "@nestjs/common";
 import type { InputJsonValue } from "@prisma/client/runtime/library";
 import { PrismaService } from "../prisma/prisma.service";
@@ -43,6 +44,8 @@ import { CreateLlmProviderDto, UpdateLlmProviderDto, LlmProviderResponseDto } fr
  */
 @Controller("llm/admin")
 export class LlmProviderAdminController {
+  private readonly logger = new Logger(LlmProviderAdminController.name);
+
   constructor(
     private readonly prisma: PrismaService,
     private readonly llmManager: LlmManagerService
@@ -245,8 +248,11 @@ export class LlmProviderAdminController {
       return {
         healthy: health.healthy,
       };
-    } catch {
+    } catch (error: unknown) {
       // Provider not loaded in manager (might be disabled)
+      const errorMessage = error instanceof Error ? error.message : String(error);
+      this.logger.warn(`Failed to test provider ${id}: ${errorMessage}`);
+
       return {
         healthy: false,
         error: "Provider not loaded in manager. Try reloading providers.",