feat(webhooks): add Deck card sync preset with vector indexing

Nextcloud Deck PR #7910 added IWebhookCompatibleEvent to CardCreated/
Updated/DeletedEvent and BoardUpdatedEvent, so Deck can finally emit
real-time webhooks via core's webhook_listeners app. Wire this into
the existing preset → parser → DocumentTask pipeline that already
backs Notes / Calendar / Tables / Forms / Files sync.

- Add deck_sync preset (app=deck, 4 events) and drop the stale
  "Deck does not support webhooks" comment.
- Teach webhook_parser to convert Deck card events into
  DocumentTask(doc_type=deck_card, operation=index|delete) with
  stack_id metadata. BoardUpdatedEvent logs delivery at INFO and
  returns None — the polling scanner reconciles affected cards.
- Cover three new unit tests for the deck create/delete/board-update
  paths plus symmetric fail-open tests for missing card.id /
  node.id in _parse_deck_event and _parse_file_event.

The astrolabe admin UI auto-discovers the new preset via
filter_presets_by_installed_apps(); no astrolabe-side wiring is
required for it to appear in the Webhook Management card grid.

Note: requires Deck ≥1.18.x (where PR #7910 lands); the preset is
hidden when the Deck app isn't installed.

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

nextcloud_mcp_server/server/webhook_presets.py

@@ -43,11 +43,18 @@ TABLES_EVENT_ROW_DELETED = "OCA\\Tables\\Event\\RowDeletedEvent"
 # Forms webhook events (Nextcloud 30+)
 FORMS_EVENT_FORM_SUBMITTED = "OCA\\Forms\\Events\\FormSubmittedEvent"
 
-# NOTE: Deck and Contacts do NOT support webhooks
-# Their event classes do not implement IWebhookCompatibleEvent interface.
-# Alternative sync strategies:
-# - Deck: Use polling with ETag-based change detection
-# - Contacts: Use CardDAV sync-token mechanism for efficient syncing
+# Deck webhook events (require nextcloud/deck PR #7910, which adds
+# IWebhookCompatibleEvent to these event classes). BoardUpdatedEvent only
+# carries a board ID and is used as a fan-out signal; the polling scanner
+# reconciles affected cards.
+DECK_EVENT_CARD_CREATED = "OCA\\Deck\\Event\\CardCreatedEvent"
+DECK_EVENT_CARD_UPDATED = "OCA\\Deck\\Event\\CardUpdatedEvent"
+DECK_EVENT_CARD_DELETED = "OCA\\Deck\\Event\\CardDeletedEvent"
+DECK_EVENT_BOARD_UPDATED = "OCA\\Deck\\Event\\BoardUpdatedEvent"
+
+# NOTE: Contacts does NOT support webhooks — its event classes do not
+# implement IWebhookCompatibleEvent. Use CardDAV sync-token mechanism for
+# efficient syncing.
 
 
 WEBHOOK_PRESETS: Dict[str, WebhookPreset] = {
@@ -138,6 +145,29 @@ WEBHOOK_PRESETS: Dict[str, WebhookPreset] = {
             },
         ],
     },
+    "deck_sync": {
+        "name": "Deck Sync",
+        "description": "Real-time synchronization for Deck cards (create, update, delete) and board updates",
+        "app": "deck",
+        "events": [
+            {
+                "event": DECK_EVENT_CARD_CREATED,
+                "filter": {},
+            },
+            {
+                "event": DECK_EVENT_CARD_UPDATED,
+                "filter": {},
+            },
+            {
+                "event": DECK_EVENT_CARD_DELETED,
+                "filter": {},
+            },
+            {
+                "event": DECK_EVENT_BOARD_UPDATED,
+                "filter": {},
+            },
+        ],
+    },
 }