feat: add package grouping UI with expand/collapse, selection, and manual grouping

- Update STL page to use listDisplayItems query for mixed package/group display
- Rewrite package-columns to handle StlTableRow union type (group headers + packages)
- Add group expand/collapse with chevron toggle and indented member rows
- Add checkbox selection with "Group N Selected" toolbar button and dialog
- Add inline group actions: rename, dissolve, send all, remove member
- Add clickable group preview thumbnail with file upload for preview images
- Extend DataTable with optional rowClassName prop for group row styling

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/app/(app)/stls/_components/stl-table.tsx

@@ -1,11 +1,17 @@
 "use client";
 
-import { useState, useCallback, useTransition } from "react";
+import { useState, useCallback, useTransition, useMemo, useRef } from "react";
 import { useRouter, usePathname, useSearchParams } from "next/navigation";
 import { toast } from "sonner";
-import { Search } from "lucide-react";
+import { Search, Layers } from "lucide-react";
 import { useDataTable } from "@/hooks/use-data-table";
-import { getPackageColumns, type PackageRow } from "./package-columns";
+import {
+  getPackageColumns,
+  type PackageRow,
+  type StlTableRow,
+  type PackageTableRow,
+  type GroupHeaderRow,
+} from "./package-columns";
 import { PackageFilesDrawer } from "./package-files-drawer";
 import { IngestionStatus } from "./ingestion-status";
 import { SkippedPackagesTab } from "./skipped-packages-tab";
@@ -14,6 +20,7 @@ import { DataTablePagination } from "@/components/shared/data-table-pagination";
 import { DataTableViewOptions } from "@/components/shared/data-table-view-options";
 import { PageHeader } from "@/components/shared/page-header";
 import { Input } from "@/components/ui/input";
+import { Button } from "@/components/ui/button";
 import {
   Select,
   SelectContent,
@@ -21,14 +28,31 @@ import {
   SelectTrigger,
   SelectValue,
 } from "@/components/ui/select";
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle,
+} from "@/components/ui/dialog";
 import { Tabs, TabsContent, TabsList, TabsTrigger } from "@/components/ui/tabs";
 import { Badge } from "@/components/ui/badge";
-import type { IngestionAccountStatus } from "@/lib/telegram/types";
+import type { DisplayItem, IngestionAccountStatus } from "@/lib/telegram/types";
 import type { SkippedRow } from "./skipped-columns";
-import { updatePackageCreator, updatePackageTags } from "../actions";
+import {
+  updatePackageCreator,
+  updatePackageTags,
+  renameGroupAction,
+  dissolveGroupAction,
+  createGroupAction,
+  removeFromGroupAction,
+  sendAllInGroupAction,
+  updateGroupPreviewAction,
+} from "../actions";
 
 interface StlTableProps {
-  data: PackageRow[];
+  data: DisplayItem[];
   pageCount: number;
   totalCount: number;
   ingestionStatus: IngestionAccountStatus[];
@@ -58,6 +82,88 @@ export function StlTable({
   const [viewPkg, setViewPkg] = useState<PackageRow | null>(null);
   const [, startTransition] = useTransition();
 
+  // Group expansion state
+  const [expandedGroups, setExpandedGroups] = useState<Set<string>>(new Set());
+
+  // Package selection state (for manual grouping)
+  const [selectedPackages, setSelectedPackages] = useState<Set<string>>(new Set());
+
+  // Create group dialog state
+  const [createGroupOpen, setCreateGroupOpen] = useState(false);
+  const [groupName, setGroupName] = useState("");
+
+  // Group preview upload ref
+  const previewInputRef = useRef<HTMLInputElement>(null);
+  const [uploadGroupId, setUploadGroupId] = useState<string | null>(null);
+
+  const toggleGroup = useCallback((groupId: string) => {
+    setExpandedGroups((prev) => {
+      const next = new Set(prev);
+      if (next.has(groupId)) {
+        next.delete(groupId);
+      } else {
+        next.add(groupId);
+      }
+      return next;
+    });
+  }, []);
+
+  const toggleSelect = useCallback((packageId: string) => {
+    setSelectedPackages((prev) => {
+      const next = new Set(prev);
+      if (next.has(packageId)) {
+        next.delete(packageId);
+      } else {
+        next.add(packageId);
+      }
+      return next;
+    });
+  }, []);
+
+  // Flatten DisplayItem[] into StlTableRow[] based on expansion state
+  const tableRows: StlTableRow[] = useMemo(() => {
+    const rows: StlTableRow[] = [];
+    for (const item of data) {
+      if (item.type === "package") {
+        rows.push({
+          ...item.data,
+          _rowType: "package" as const,
+          _groupId: null,
+          _isGroupMember: false,
+        });
+      } else {
+        const group = item.data;
+        const isExpanded = expandedGroups.has(group.id);
+        rows.push({
+          _rowType: "group" as const,
+          id: group.id,
+          name: group.name,
+          hasPreview: group.hasPreview,
+          totalFileSize: group.totalFileSize,
+          totalFileCount: group.totalFileCount,
+          packageCount: group.packageCount,
+          combinedTags: group.combinedTags,
+          archiveTypes: group.archiveTypes,
+          latestIndexedAt: group.latestIndexedAt,
+          sourceChannel: group.sourceChannel,
+          _expanded: isExpanded,
+        });
+        if (isExpanded) {
+          for (const pkg of group.packages) {
+            rows.push({
+              ...pkg,
+              _rowType: "package" as const,
+              _groupId: group.id,
+              _isGroupMember: true,
+              packageGroupId: group.id,
+            });
+          }
+        }
+      }
+    }
+    return rows;
+  }, [data, expandedGroups]);
+
   const updateSearch = useCallback(
     (value: string) => {
       setSearchValue(value);
@@ -103,6 +209,131 @@ export function StlTable({
     [router, pathname, searchParams]
   );
 
+  const handleRenameGroup = useCallback(
+    (groupId: string, currentName: string) => {
+      const value = prompt("Enter group name:", currentName);
+      if (value === null || value.trim() === currentName) return;
+      startTransition(async () => {
+        const result = await renameGroupAction(groupId, value);
+        if (result.success) {
+          toast.success(`Group renamed to "${value.trim()}"`);
+          router.refresh();
+        } else {
+          toast.error(result.error);
+        }
+      });
+    },
+    [router]
+  );
+
+  const handleDissolveGroup = useCallback(
+    (groupId: string) => {
+      if (!confirm("Dissolve this group? Packages will become standalone items.")) return;
+      startTransition(async () => {
+        const result = await dissolveGroupAction(groupId);
+        if (result.success) {
+          toast.success("Group dissolved");
+          setExpandedGroups((prev) => {
+            const next = new Set(prev);
+            next.delete(groupId);
+            return next;
+          });
+          router.refresh();
+        } else {
+          toast.error(result.error);
+        }
+      });
+    },
+    [router]
+  );
+
+  const handleSendAllInGroup = useCallback(
+    (groupId: string) => {
+      if (!confirm("Send all packages in this group to your Telegram?")) return;
+      startTransition(async () => {
+        const result = await sendAllInGroupAction(groupId);
+        if (result.success) {
+          toast.success("Group packages queued for sending");
+          router.refresh();
+        } else {
+          toast.error(result.error);
+        }
+      });
+    },
+    [router]
+  );
+
+  const handleRemoveFromGroup = useCallback(
+    (packageId: string) => {
+      startTransition(async () => {
+        const result = await removeFromGroupAction(packageId);
+        if (result.success) {
+          toast.success("Package removed from group");
+          router.refresh();
+        } else {
+          toast.error(result.error);
+        }
+      });
+    },
+    [router]
+  );
+
+  const handleCreateGroup = useCallback(() => {
+    if (selectedPackages.size < 2) return;
+    setGroupName("");
+    setCreateGroupOpen(true);
+  }, [selectedPackages.size]);
+
+  const submitCreateGroup = useCallback(() => {
+    if (!groupName.trim() || selectedPackages.size < 2) return;
+    const ids = Array.from(selectedPackages);
+    startTransition(async () => {
+      const result = await createGroupAction(groupName, ids);
+      if (result.success) {
+        toast.success(`Group "${groupName.trim()}" created`);
+        setSelectedPackages(new Set());
+        setCreateGroupOpen(false);
+        router.refresh();
+      } else {
+        toast.error(result.error);
+      }
+    });
+  }, [groupName, selectedPackages, router]);
+
+  // Group preview upload handler (Task 12)
+  const handleGroupPreviewUpload = useCallback((groupId: string) => {
+    setUploadGroupId(groupId);
+    // Trigger file input after state update
+    setTimeout(() => {
+      previewInputRef.current?.click();
+    }, 0);
+  }, []);
+
+  const handlePreviewFileChange = useCallback(
+    (e: React.ChangeEvent<HTMLInputElement>) => {
+      const file = e.target.files?.[0];
+      if (!file || !uploadGroupId) return;
+
+      const formData = new FormData();
+      formData.append("file", file);
+
+      startTransition(async () => {
+        const result = await updateGroupPreviewAction(uploadGroupId, formData);
+        if (result.success) {
+          toast.success("Group preview updated");
+          router.refresh();
+        } else {
+          toast.error(result.error);
+        }
+        setUploadGroupId(null);
+      });
+
+      // Reset input so the same file can be selected again
+      e.target.value = "";
+    },
+    [uploadGroupId, router]
+  );
+
   const columns = getPackageColumns({
     onViewFiles: (pkg) => setViewPkg(pkg),
     searchTerm,
@@ -136,9 +367,17 @@ export function StlTable({
         }
       });
     },
+    onToggleGroup: toggleGroup,
+    onRenameGroup: handleRenameGroup,
+    onDissolveGroup: handleDissolveGroup,
+    onSendAllInGroup: handleSendAllInGroup,
+    onRemoveFromGroup: handleRemoveFromGroup,
+    onGroupPreviewUpload: handleGroupPreviewUpload,
+    selectedPackages,
+    onToggleSelect: toggleSelect,
   });
 
-  const { table } = useDataTable({ data, columns, pageCount });
+  const { table } = useDataTable({ data: tableRows, columns, pageCount });
 
   const activeTag = searchParams.get("tag") ?? "";
 
@@ -191,11 +430,37 @@ export function StlTable({
               </Select>
             )}
             <DataTableViewOptions table={table} />
+            {selectedPackages.size >= 2 && (
+              <Button
+                variant="outline"
+                size="sm"
+                className="h-9 gap-1.5"
+                onClick={handleCreateGroup}
+              >
+                <Layers className="h-3.5 w-3.5" />
+                Group {selectedPackages.size} Selected
+              </Button>
+            )}
+            {selectedPackages.size > 0 && selectedPackages.size < 2 && (
+              <span className="text-xs text-muted-foreground">
+                Select at least 2 packages to group
+              </span>
+            )}
           </div>
 
           <DataTable
             table={table}
             emptyMessage="No packages found. Archives will appear here after ingestion."
+            rowClassName={(row) => {
+              const data = row.original as StlTableRow;
+              if (data._rowType === "group") {
+                return "bg-muted/30 border-border";
+              }
+              if (data._rowType === "package" && (data as PackageTableRow)._isGroupMember) {
+                return "bg-muted/10";
+              }
+              return "";
+            }}
           />
           <DataTablePagination table={table} totalCount={totalCount} />
         </TabsContent>
@@ -217,6 +482,47 @@ export function StlTable({
         }}
         highlightTerm={searchTerm}
       />
+
+      {/* Create Group Dialog */}
+      <Dialog open={createGroupOpen} onOpenChange={setCreateGroupOpen}>
+        <DialogContent className="sm:max-w-md">
+          <DialogHeader>
+            <DialogTitle>Create Package Group</DialogTitle>
+            <DialogDescription>
+              Group {selectedPackages.size} selected packages together. Enter a name for the group.
+            </DialogDescription>
+          </DialogHeader>
+          <div className="py-4">
+            <Input
+              placeholder="Group name..."
+              value={groupName}
+              onChange={(e) => setGroupName(e.target.value)}
+              onKeyDown={(e) => {
+                if (e.key === "Enter") submitCreateGroup();
+              }}
+              autoFocus
+            />
+          </div>
+          <DialogFooter>
+            <Button variant="outline" onClick={() => setCreateGroupOpen(false)}>
+              Cancel
+            </Button>
+            <Button onClick={submitCreateGroup} disabled={!groupName.trim()}>
+              <Layers className="h-4 w-4 mr-1" />
+              Create Group
+            </Button>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+
+      {/* Hidden file input for group preview upload (Task 12) */}
+      <input
+        ref={previewInputRef}
+        type="file"
+        accept="image/jpeg,image/png,image/webp"
+        className="hidden"
+        onChange={handlePreviewFileChange}
+      />
     </div>
   );
 }