Problem

gog docs write --replace --markdown --pageless flips documentFormat.documentMode = PAGELESS correctly (thank you for #593) — but leaves documentStyle.pageSize.width at the default 612pt (US Letter). In pageless mode, content (especially tables) still respects pageSize.width as the content width, so tables render narrow on a wide screen.

Repro (v0.18.0)

gog docs write <docId> --replace --markdown --pageless --file=some-table-doc.md
gog docs raw <docId> | jq '.documentStyle | {pageSize, marginLeft, marginRight, documentFormat}'
# Output:
# {
#   "pageSize":     { "width":  { "magnitude": 612, "unit": "PT" }, "height": ... },
#   "marginLeft":   { "magnitude": 72, "unit": "PT" },
#   "marginRight":  { "magnitude": 72, "unit": "PT" },
#   "documentFormat": { "documentMode": "PAGELESS" }
# }

Effective content width = 612 − 72 − 72 = 468pt (≈6.5″) even though the doc is pageless.

Proposed fix

Either:

1. Default to wider pageSize when --pageless is set — e.g. 1080pt × 792pt with 36pt L/R margins. Matches what Google Docs UI does when a user creates a fresh pageless doc.
2. Add --page-width=<PT> and --margin-lr=<PT> flags on docs write and docs page-layout — explicit control. See companion issue for margins.

Workaround today

Follow --pageless with a Docs API updateDocumentStyle batchUpdate to widen pageSize.width.

v0.18.0 verified

• gog docs write --replace --markdown --pageless does not widen.
• gog docs page-layout --layout=pageless does not widen either.