getSpreadsheet loads metadata without grid cell values. Use it to discover
immutable sheet and table IDs or inspect spreadsheet settings.
Example
Inputs
spreadsheet: string is required. account optionally selects the Google
account; all action inputs accept compatible signals.
Output
Returns aSpreadsheet with spreadsheetId, title, url, optional locale,
timeZone, and autoRecalc, plus namedRanges and sheets. Each sheet includes
sheetId, title, zero-based index, sheetType, hidden, rightToLeft,
frozen and allocated row/column counts, and native tables. Named and table
ranges use zero-based, end-exclusive startRowIndex, endRowIndex,
startColumnIndex, and endColumnIndex with sheetId.