feat(import): add real-time progress tracking for CSV imports

templates/import.html

@@ -432,6 +432,8 @@ document.addEventListener('DOMContentLoaded', function() {
     setTimeout(() => {
         document.getElementById('uploadMode').value = 'batch';
         switchUploadMode();
+        // Resume progress monitoring if a batch is already running for this user
+        resumeBatchProgressIfRunning();
     }, 100);
 });
 
@@ -857,20 +859,109 @@ function displayImportResults(result) {
     panel.classList.remove('hidden');
 }
 
-function showProgress(show, message = '') {
+function showProgress(show, message = '', percent = null) {
     const panel = document.getElementById('progressPanel');
     const status = document.getElementById('progressStatus');
     const bar = document.getElementById('progressBar');
     
     if (show) {
         status.textContent = message;
-        bar.style.width = '100%';
+        if (percent === null || isNaN(percent)) {
+            bar.style.width = '100%';
+        } else {
+            const clamped = Math.max(0, Math.min(100, Number(percent)));
+            bar.style.width = clamped + '%';
+        }
         panel.classList.remove('hidden');
     } else {
         panel.classList.add('hidden');
     }
 }
 
+// -----------------------------
+// Batch progress monitoring
+// -----------------------------
+const TERMINAL_BATCH_STATUSES = new Set(['success', 'completed_with_errors', 'failed']);
+let batchProgress = { timer: null, auditId: null };
+
+async function fetchCurrentBatch() {
+    try {
+        const resp = await window.http.wrappedFetch('/api/import/current-batch');
+        if (!resp.ok) return null;
+        const json = await resp.json();
+        return json && json.running ? json : null;
+    } catch (_) { return null; }
+}
+
+function stopBatchProgressPolling() {
+    if (batchProgress.timer) {
+        clearInterval(batchProgress.timer);
+        batchProgress.timer = null;
+    }
+    batchProgress.auditId = null;
+}
+
+async function pollBatchProgressOnce(auditId) {
+    try {
+        const resp = await window.http.wrappedFetch(`/api/import/batch-progress/${encodeURIComponent(auditId)}`);
+        if (!resp.ok) return;
+        const p = await resp.json();
+        const percent = Number(p.percent || 0);
+        const total = Number(p.total_files || 0);
+        const processed = Number(p.processed_files || 0);
+        const status = String(p.status || 'running');
+        const statusNice = status.replaceAll('_', ' ');
+        const msg = total > 0
+            ? `Processing ${processed}/${total} (${percent.toFixed(1)}%) · ${statusNice}`
+            : `Processing… ${statusNice}`;
+        showProgress(true, msg, percent);
+        if (TERMINAL_BATCH_STATUSES.has(status)) {
+            stopBatchProgressPolling();
+        }
+    } catch (_) { /* ignore */ }
+}
+
+function startBatchProgressPolling(auditId) {
+    stopBatchProgressPolling();
+    batchProgress.auditId = auditId;
+    // immediate + interval polling
+    pollBatchProgressOnce(auditId);
+    batchProgress.timer = setInterval(() => pollBatchProgressOnce(auditId), 1500);
+}
+
+async function ensureAuditIdWithRetry(maxAttempts = 10, delayMs = 500) {
+    for (let attempt = 0; attempt < maxAttempts; attempt++) {
+        const cur = await fetchCurrentBatch();
+        if (cur && cur.audit_id) return cur.audit_id;
+        await new Promise(r => setTimeout(r, delayMs));
+    }
+    return null;
+}
+
+async function monitorBatchProgressDuring(promise) {
+    try {
+        const id = await ensureAuditIdWithRetry();
+        if (id) {
+            startBatchProgressPolling(id);
+        }
+    } catch (_) {}
+    try {
+        await promise; // wait for upload completion
+    } finally {
+        stopBatchProgressPolling();
+    }
+}
+
+async function resumeBatchProgressIfRunning() {
+    try {
+        const cur = await fetchCurrentBatch();
+        if (cur && cur.audit_id) {
+            showProgress(true, 'Resuming import progress…', 0);
+            startBatchProgressPolling(cur.audit_id);
+        }
+    } catch (_) {}
+}
+
 async function clearTable() {
     const fileType = document.getElementById('clearTableType').value;
     
@@ -1389,12 +1480,14 @@ async function handleBatchImport(event) {
     formData.append('replace_existing', replaceExisting);
     
     try {
-        showProgress(true, 'Processing batch import...');
-        
-    const response = await window.http.wrappedFetch('/api/import/batch-upload', {
-        method: 'POST',
-        body: formData
-    });
+        showProgress(true, 'Processing batch import...', 0);
+        // Kick off upload and monitor progress concurrently
+        const uploadPromise = window.http.wrappedFetch('/api/import/batch-upload', {
+            method: 'POST',
+            body: formData
+        });
+        monitorBatchProgressDuring(uploadPromise);
+        const response = await uploadPromise;
         
         if (!response.ok) {
             const error = await response.json();