feat(import-ui): deep scan button, sticky settings tabs, tasks-above-filters, fix Scanning-undefined source_path — Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/src/stores/import.js

@@ -52,25 +52,31 @@ export const useImportStore = defineStore('import', () => {
     }
   }
 
-  async function triggerScan() {
+  async function triggerScan(mode = 'quick') {
+    if (!['quick', 'deep', 'verify'].includes(mode)) {
+      throw new Error(`unsupported scan mode: ${mode}`)
+    }
     triggerError.value = null
     try {
-      await api.post('/api/import/trigger', { body: { mode: 'quick' } })
+      await api.post('/api/import/trigger', { body: { mode } })
       // Acknowledge immediately so the click isn't invisible. scan_directory
       // can finalize the batch synchronously when every file in /import is
       // already on a non-failed ImportTask (operator-flagged 2026-05-25:
       // 233k existing tasks → all paths in skip-set → files_seen=0 →
       // batch flashes 'running' for <100ms then 'complete' before the
       // first refreshStatus() lands; UI never sees the active state).
-      window.__fcToast?.({ text: 'Scan triggered', type: 'success' })
+      const label = mode === 'deep'
+        ? 'Deep scan triggered (pHash backfill chained)'
+        : mode === 'verify' ? 'Library verify triggered' : 'Quick scan triggered'
+      window.__fcToast?.({ text: label, type: 'success' })
       await refreshStatus()
       // Re-poll twice over ~5s to catch quick-finalize transitions and
-      // surface a result toast either way.
+      // surface a result toast either way. Skip the "no new files" hint
+      // for 'verify' since it doesn't walk the import_root.
       setTimeout(async () => {
         await refreshStatus()
-        if (!activeBatch.value) {
-          // Either scan completed with zero new files, or it never visibly
-          // started. Fetch the freshest task to differentiate.
+        await loadTasks(true)
+        if (!activeBatch.value && mode !== 'verify') {
           window.__fcToast?.({
             text: 'Scan complete — no new files (everything already on an ImportTask row)',
             type: 'info',