tools/documents: add document tools over capped tool results

A tool result stays whole in its own tool message; a request-prep marker
names a document_id (the message's tool_call_id). read_document,
search_document, document_info, and list_documents resolve that id back to
the message body, so reading and searching a capped result needs no re-run.

The store binds on the host instance and reads the agent's live history,
which carries whole results and re-reads whatever a resume reloaded.

Co-authored-by: CommandCodeBot <noreply@commandcode.ai>

tests/test_tools/test_catalog.py

@@ -61,6 +61,10 @@ def test_read_only_classification() -> None:
         "read_file",
         "view_image",
         "get_truncated",
+        "read_document",
+        "search_document",
+        "document_info",
+        "list_documents",
         "glob_paths",
         "regex_files",
         "listdir",