fix(scan): Fix-mode scanner + dialog suppression + cancel/timer + importer revive

- scan.jsx: app.beginSuppressDialogs() + clean quit (no AE hang on font/footage
  dialogs); FIX-mode branch parses frl_c(x)t/m(y) layer names → scenes by c(x);
  flexible/mockup keep comp-based walk; FR_SCAN_MODE selects.
- render-svc: scan job carries project mode; cancel endpoint + node watchdog that
  kills AE on cancel; parseObjectURL handles minio:// (bucket in host); scan with
  no template fails cleanly; status guards so late results can't un-cancel.
- content importer: revive soft-deleted scenes instead of duplicate-inserting
  (fixes scenes_project_id_key unique violation); orphan diff ignores deleted.
- admin: scan dialog gets project-type picker + elapsed timer + Cancel button.
- node-agent: AE-2026 wiring (host port 5010, host-reachable presign endpoint),
  FR_SCAN_MODE plumbing. docs/aep-template-convention.md: per-type naming + bundles.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

services/content/FlatRender.ContentSvc/Application/Services/AepImportService.cs

@@ -21,8 +21,11 @@ public class AepImportService(ContentDbContext db)
 
     private async Task<ImportDiff> RunAsync(Guid projectId, ScanResult scan, ScanApplyOptions? apply)
     {
+        // Load ALL scenes incl. soft-deleted: the UNIQUE(project_id,key) constraint
+        // covers deleted rows too, so a re-scan must REVIVE a soft-deleted match
+        // rather than insert a duplicate (which would violate the constraint).
         var existing = await db.Scenes
-            .Where(s => s.ProjectId == projectId && s.DeletedAt == null)
+            .Where(s => s.ProjectId == projectId)
             .Include(s => s.ContentElements)
             .Include(s => s.ColorElements)
             .ToListAsync();
@@ -74,13 +77,19 @@ public class AepImportService(ContentDbContext db)
                     scene = new Scene { ProjectId = projectId, Key = ss.Key, Sort = ss.Sort ?? sortBase++ };
                     db.Scenes.Add(scene);
                 }
+                else if (scene!.DeletedAt is not null)
+                {
+                    scene.DeletedAt = null; // revive a soft-deleted scene the scan re-discovered
+                }
                 ApplySceneHeader(scene!, ss, isNew, apply);
                 ApplyElements(scene!, scElems, exElemByKey, scElemKeys, apply);
                 ApplyColors(scene!, scColors, exColorByKey, scColorKeys, apply);
             }
         }
 
-        var orphans = existing.Where(s => !scanKeys.Contains(s.Key)).ToList();
+        // Orphans = currently-active scenes the scan no longer contains (ignore
+        // already soft-deleted rows so they don't inflate the diff).
+        var orphans = existing.Where(s => s.DeletedAt == null && !scanKeys.Contains(s.Key)).ToList();
         if (apply is not null && apply.RemoveOrphanScenes)
             foreach (var s in orphans) s.DeletedAt = DateTime.UtcNow;