perf: optimize bulk XML upload for 100k+ files

Backend:
- Add batch insert using multi-row INSERT with ON CONFLICT
- Process in batches of 500 records for optimal DB performance
- Return detailed batch results (inserted, duplicates, errors)

Frontend:
- Parse files in chunks of 500 to prevent memory issues
- Upload in batches of 200 CFDIs per request
- Add detailed progress bar with real-time stats
- Show upload statistics (loaded, duplicates, errors)
- Add cancel functionality during upload
- Refresh data after upload completes

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

apps/web/lib/api/cfdi.ts

@@ -61,8 +61,28 @@ export async function createCfdi(data: CreateCfdiData): Promise<Cfdi> {
   return response.data;
 }
 
-export async function createManyCfdis(cfdis: CreateCfdiData[]): Promise<{ count: number }> {
-  const response = await apiClient.post<{ count: number; message: string }>('/cfdi/bulk', { cfdis });
+export interface BatchUploadResult {
+  message: string;
+  batchNumber: number;
+  totalBatches: number;
+  inserted: number;
+  duplicates: number;
+  errors: number;
+  errorMessages?: string[];
+}
+
+export async function createManyCfdis(
+  cfdis: CreateCfdiData[],
+  batchNumber?: number,
+  totalBatches?: number,
+  totalFiles?: number
+): Promise<BatchUploadResult> {
+  const response = await apiClient.post<BatchUploadResult>('/cfdi/bulk', {
+    cfdis,
+    batchNumber: batchNumber || 1,
+    totalBatches: totalBatches || 1,
+    totalFiles: totalFiles || cfdis.length
+  });
   return response.data;
 }