fix(webhooks): wire receiver to vector sync queue and fix registered URI

The /webhooks/nextcloud endpoint was a no-op stub that logged the
payload and returned 200 OK; webhook deletions never reached Qdrant.
Compounding that, _get_webhook_uri() registered the docker-compose
internal hostname (http://mcp:8000) with Nextcloud whenever
/.dockerenv existed — including ECS Fargate — so cloud deployments
were registering a URL NC could not resolve.

- New vector/webhook_parser.py extracts a DocumentTask from
  NodeCreatedEvent / NodeWrittenEvent / BeforeNodeDeletedEvent
  payloads scoped to */files/Notes/*.md (matching the registered
  preset filters).
- New vector/webhook_receiver.py pushes that task onto the same
  send-stream the scanner uses (app.state.document_send_stream),
  with 503 when sync is not running so NC retries delivery.
- _get_webhook_uri() now prefers NEXTCLOUD_MCP_SERVER_URL over the
  /.dockerenv branch, so the explicit public URL set on cloud tasks
  wins; docker-compose dev still falls back to the internal name when
  no public URL is configured.

Calendar / Tables event parsing is intentionally out of scope here.

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

tests/unit/test_webhook_parser.py

@@ -0,0 +1,188 @@
+"""Unit tests for the Nextcloud webhook payload parser.
+
+Payload examples are taken from real Nextcloud captures recorded in
+``webhook-testing-findings.md``.
+"""
+
+import pytest
+
+from nextcloud_mcp_server.vector.webhook_parser import extract_document_task
+
+
+@pytest.mark.unit
+def test_node_created_event_returns_index_task():
+    payload = {
+        "user": {"uid": "admin", "displayName": "admin"},
+        "time": 1762850245,
+        "event": {
+            "class": "OCP\\Files\\Events\\Node\\NodeCreatedEvent",
+            "node": {
+                "id": 437,
+                "path": "/admin/files/Notes/Webhooks/Webhook Test Note.md",
+            },
+        },
+    }
+
+    task = extract_document_task(payload)
+
+    assert task is not None
+    assert task.user_id == "admin"
+    assert task.doc_id == "437"
+    assert task.doc_type == "note"
+    assert task.operation == "index"
+    assert task.modified_at == 1762850245
+
+
+@pytest.mark.unit
+def test_node_written_event_returns_index_task():
+    payload = {
+        "user": {"uid": "admin", "displayName": "admin"},
+        "time": 1762850960,
+        "event": {
+            "class": "OCP\\Files\\Events\\Node\\NodeWrittenEvent",
+            "node": {
+                "id": 437,
+                "path": "/admin/files/Notes/Webhooks/Webhook Test Note.md",
+            },
+        },
+    }
+
+    task = extract_document_task(payload)
+
+    assert task is not None
+    assert task.operation == "index"
+    assert task.doc_id == "437"
+
+
+@pytest.mark.unit
+def test_before_node_deleted_event_returns_delete_task():
+    payload = {
+        "user": {"uid": "alice", "displayName": "Alice"},
+        "time": 1762851093,
+        "event": {
+            "class": "OCP\\Files\\Events\\Node\\BeforeNodeDeletedEvent",
+            "node": {
+                "id": 437,
+                "path": "/alice/files/Notes/Webhooks/Webhook Test Note.md",
+            },
+        },
+    }
+
+    task = extract_document_task(payload)
+
+    assert task is not None
+    assert task.user_id == "alice"
+    assert task.operation == "delete"
+    assert task.doc_id == "437"
+    assert task.doc_type == "note"
+
+
+@pytest.mark.unit
+def test_node_id_is_normalized_to_string():
+    """NC sends node.id as int; we always emit str (per ADR-010 §A.3)."""
+    payload = {
+        "user": {"uid": "admin"},
+        "time": 1,
+        "event": {
+            "class": "OCP\\Files\\Events\\Node\\NodeCreatedEvent",
+            "node": {"id": 437, "path": "/admin/files/Notes/foo.md"},
+        },
+    }
+
+    task = extract_document_task(payload)
+
+    assert task is not None
+    assert isinstance(task.doc_id, str)
+    assert task.doc_id == "437"
+
+
+@pytest.mark.unit
+def test_path_outside_notes_returns_none():
+    payload = {
+        "user": {"uid": "admin"},
+        "time": 1,
+        "event": {
+            "class": "OCP\\Files\\Events\\Node\\NodeCreatedEvent",
+            "node": {"id": 1, "path": "/admin/files/Documents/foo.md"},
+        },
+    }
+
+    assert extract_document_task(payload) is None
+
+
+@pytest.mark.unit
+def test_non_markdown_inside_notes_returns_none():
+    payload = {
+        "user": {"uid": "admin"},
+        "time": 1,
+        "event": {
+            "class": "OCP\\Files\\Events\\Node\\NodeCreatedEvent",
+            "node": {"id": 1, "path": "/admin/files/Notes/image.png"},
+        },
+    }
+
+    assert extract_document_task(payload) is None
+
+
+@pytest.mark.unit
+def test_parent_folder_event_returns_none():
+    """Creating a note fires events for the parent folder too — ignore those."""
+    payload = {
+        "user": {"uid": "admin"},
+        "time": 1,
+        "event": {
+            "class": "OCP\\Files\\Events\\Node\\NodeCreatedEvent",
+            "node": {"id": 100, "path": "/admin/files/Notes/Webhooks"},
+        },
+    }
+
+    assert extract_document_task(payload) is None
+
+
+@pytest.mark.unit
+def test_unknown_event_class_returns_none():
+    payload = {
+        "user": {"uid": "admin"},
+        "time": 1,
+        "event": {
+            "class": "OCP\\Calendar\\Events\\CalendarObjectCreatedEvent",
+            "objectData": {"id": 7, "uri": "x.ics"},
+        },
+    }
+
+    assert extract_document_task(payload) is None
+
+
+@pytest.mark.unit
+def test_node_deleted_event_without_id_returns_none():
+    """``NodeDeletedEvent`` (no node.id) is not the registered event, but if
+    one ever leaks through we ignore it rather than guess at the doc_id —
+    the polling scanner will catch up via its grace period."""
+    payload = {
+        "user": {"uid": "admin"},
+        "time": 1,
+        "event": {
+            "class": "OCP\\Files\\Events\\Node\\BeforeNodeDeletedEvent",
+            "node": {"path": "/admin/files/Notes/foo.md"},
+        },
+    }
+
+    assert extract_document_task(payload) is None
+
+
+@pytest.mark.unit
+def test_missing_user_field_returns_none():
+    payload = {
+        "time": 1,
+        "event": {
+            "class": "OCP\\Files\\Events\\Node\\NodeCreatedEvent",
+            "node": {"id": 1, "path": "/admin/files/Notes/foo.md"},
+        },
+    }
+
+    assert extract_document_task(payload) is None
+
+
+@pytest.mark.unit
+def test_empty_payload_returns_none():
+    assert extract_document_task({}) is None