feat(ops): show upload percent, speed and ETA for ingest files

The ingest upload used fetch(), which cannot report request-body
progress, so the only feedback was a static "Cargando…" label — no way
to tell a stalled 2 GB upload from a working one.

Switch uploadFile() to XMLHttpRequest and expose an optional onProgress
callback reporting loaded/total bytes, a smoothed transfer rate and a
remaining-time estimate. The Operaciones ingest table renders a progress
bar row under the file being uploaded. Once the bytes are all sent the
server still has to write the file, so that tail reads "Procesando en el
servidor…" rather than parking at 100%.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

apps/web/src/app/globals.css

@@ -837,6 +837,46 @@ button {
   display: inline-block;
 }
 
+/* Upload progress (Operaciones ingest) */
+.upload-progress {
+  display: flex;
+  flex-direction: column;
+  gap: 6px;
+  padding: 4px 0 8px;
+}
+.progress-track {
+  position: relative;
+  overflow: hidden;
+  height: 8px;
+  border-radius: 999px;
+  background: var(--paper-2);
+}
+.progress-fill {
+  height: 100%;
+  border-radius: 999px;
+  background: var(--brand-500);
+  transition: width 0.2s linear;
+}
+.progress-indeterminate .progress-fill {
+  width: 40% !important;
+  animation: progress-slide 1.2s var(--ease-out-quart) infinite;
+}
+@keyframes progress-slide {
+  0% {
+    transform: translateX(-100%);
+  }
+  100% {
+    transform: translateX(250%);
+  }
+}
+.upload-progress-stats {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 12px;
+  font-size: 12px;
+  color: var(--muted);
+}
+
 @keyframes shimmer {
   0% {
     background-position: -420px 0;