feat(kanban): archive automatico para cards Done +30 dias (issue 0092)

Adds an archive layer separate from the trash. Cards in is_done columns
that have been there for more than 30 days are auto-archived on the next
board load (throttled to once every 30 minutes). Archived cards leave
the board but stay in the DB and are listed in a new sidebar drawer
"Hecho (archivo)" below the existing Papelera, with a one-click restore.

Schema (migration 012_card_archived.sql):
- ALTER TABLE cards ADD COLUMN archived_at TEXT;
- NULL = active, ISO timestamp = archived. Independent from deleted_at.

Backend:
- Card.ArchivedAt + JSON; ListCardsWithTime filters archived_at IS NULL.
- New methods: ArchiveCard, UnarchiveCard, ListArchivedCards,
  AutoArchiveDoneOlderThan.
- New endpoints: GET /api/archive, POST /api/cards/:id/archive,
  POST /api/cards/:id/unarchive.
- handleGetBoard invokes maybeAutoArchive (atomic throttle, 30 min sweep,
  30 day cutoff). Errors logged but never block the board response.

Frontend:
- Card type + api.ts add the new field and helpers.
- App.tsx state for archive list, reload, archive/unarchive handlers.
- New sidebar drawer with toggle, count badge, restore button.
- KanbanCard gains an "Archivar" menu item (gated on isDone +
  onArchive prop) for manual archiving of any done card.

Tests:
- Playwright e2e/archive.spec.ts: manual archive via menu, drawer
  toggle, unarchive. Picks a done card via /api/board introspection so
  it stays stable regardless of board state.
- Auto-archive of >30d cards: not under e2e (real time travel needed);
  covered by code review of the SQL query and the throttle.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/src/components/KanbanCard.tsx

@@ -15,6 +15,7 @@ import {
   Tooltip,
 } from "@mantine/core";
 import {
+  IconArchive,
   IconCalendarDue,
   IconCheck,
   IconClock,
@@ -50,6 +51,7 @@ interface Props {
   onAssign: (id: string, assignee_id: string | null) => void;
   onSetDeadline?: (id: string, deadline: string | null) => void;
   onSetRequester?: (id: string, requester: string) => void;
+  onArchive?: (id: string) => void;
   requesterOptions?: string[];
   onOpenCustomColor?: (cardId: string, current: string) => void;
   activeSticker?: string | null;
@@ -100,6 +102,7 @@ interface CardBodyProps {
   onAssign: (id: string, assignee_id: string | null) => void;
   onSetDeadline?: (id: string, deadline: string | null) => void;
   onSetRequester?: (id: string, requester: string) => void;
+  onArchive?: (id: string) => void;
   onOpenCustomColor?: (cardId: string, current: string) => void;
   onRemoveSticker?: (cardId: string, index: number) => void;
   onMoveSticker?: (cardId: string, index: number, x: number, y: number) => void;
@@ -127,6 +130,7 @@ const KanbanCardBody = memo(function KanbanCardBody({
   onAssign,
   onSetDeadline,
   onSetRequester,
+  onArchive,
   onOpenCustomColor,
   onRemoveSticker,
   onMoveSticker,
@@ -321,6 +325,15 @@ const KanbanCardBody = memo(function KanbanCardBody({
           </Popover.Dropdown>
         </Popover>
       )}
+      {isDone && onArchive && (
+        <Menu.Item
+          leftSection={<IconArchive size={14} />}
+          color="teal"
+          onClick={() => { setMenuOpen(false); onArchive(card.id); }}
+        >
+          Archivar
+        </Menu.Item>
+      )}
       <Menu.Divider />
       <Menu.Item leftSection={<IconTrash size={14} />} color="red" onClick={() => { setMenuOpen(false); onDelete(card.id); }}>Borrar</Menu.Item>
     </>
@@ -463,6 +476,7 @@ function KanbanCardImpl({
   onAssign,
   onSetDeadline,
   onSetRequester,
+  onArchive,
   requesterOptions,
   onOpenCustomColor,
   activeSticker,
@@ -593,6 +607,7 @@ function KanbanCardImpl({
         onAssign={onAssign}
         onSetDeadline={onSetDeadline}
         onSetRequester={onSetRequester}
+        onArchive={onArchive}
         onOpenCustomColor={onOpenCustomColor}
         onRemoveSticker={onRemoveSticker}
         onMoveSticker={onMoveSticker}

frontend/src/components/KanbanColumn.tsx

@@ -82,6 +82,7 @@ interface Props {
   onAssignCard: (id: string, assignee_id: string | null) => void;
   onSetCardDeadline?: (id: string, deadline: string | null) => void;
   onSetRequester?: (id: string, requester: string) => void;
+  onArchiveCard?: (id: string) => void;
   requesterOptions?: string[];
   onOpenCustomCardColor?: (cardId: string, current: string) => void;
   activeSticker?: string | null;
@@ -117,6 +118,7 @@ function KanbanColumnImpl({
   onAssignCard,
   onSetCardDeadline,
   onSetRequester,
+  onArchiveCard,
   requesterOptions,
   onOpenCustomCardColor,
   activeSticker,
@@ -593,6 +595,7 @@ function KanbanColumnImpl({
                     onAssign={onAssignCard}
                     onSetDeadline={onSetCardDeadline}
                     onSetRequester={onSetRequester}
+                    onArchive={onArchiveCard}
                     requesterOptions={requesterOptions}
                     onOpenCustomColor={onOpenCustomCardColor}
                     users={users}