Synced from sheet-skill-spec canonical (cli:table_put schema +
references). +table-put/+workbook-create accept the new shape via a
tableSheetIn -> tableSheetSpec normalize step (dtype string -> internal
type/format mapping). +table-get emits the same shape so the writer's
df_to_sheet and the reader's sheet_to_df round-trip cleanly.
isoDateToSerial now accepts the full ISO datetime form
(2024-01-15T00:00:00.000, including timezone suffixes) emitted by
df.to_json(date_format="iso"), not just yyyy-mm-dd. End-to-end verified
by the spec repo's contracts/python_helper_roundtrip script against a
real Lark spreadsheet on pandas 2.2 and 3.0.
c8de4e3692