feat(wiki): convert existing source to wiki + human page edit endpoint

Unit 5 of F-Wiki (D20-D23). convert_source_to_wiki task reuses reingest's storage file-load + parser to materialize files->wiki_pages (one page/file), skips/reports non-text, re-embeds per page, and flips kind=wiki + exposure=agentic_tool only when pages were created. POST /wiki/convert (explicit, write-authz; blank source enables inline, fileful enqueues the task; rejects mid-ingest). PUT /wiki/page for human edits (write-authz, optimistic version -> 409, re-embed). PATCH /config preserves kind (kind changes only via convert).

tests/api/user/test_tasks.py

@@ -86,6 +86,20 @@ class TestReingestSourceTask:
         assert result == {"status": "ok"}
 
 
+class TestConvertSourceToWikiTask:
+    @pytest.mark.unit
+    @patch("application.worker.convert_source_to_wiki_worker")
+    def test_calls_convert_worker(self, mock_worker):
+        from application.api.user.tasks import convert_source_to_wiki
+
+        mock_worker.return_value = {"status": "converted"}
+
+        result = convert_source_to_wiki("source123", "user1")
+
+        mock_worker.assert_called_once_with(ANY, "source123", "user1")
+        assert result == {"status": "converted"}
+
+
 class TestScheduleSyncsTask:
     @pytest.mark.unit
     @patch("application.api.user.tasks.sync_worker")
@@ -286,6 +300,8 @@ class TestDurableTaskRetryPolicy:
             "store_attachment",
             "process_agent_webhook",
             "ingest_connector_task",
+            "reembed_wiki_page",
+            "convert_source_to_wiki",
         ],
     )
     def test_task_has_retry_config(self, task_name):