docs: name the page cursor property as Python spells it

[razor-x]

The pagination heading in the README called the cursor nextPageCursor, which is how the JavaScript SDK spells it. This SDK exposes it as pagination.next_page_cursor (seam/resources/pagination.py), and the example directly under that heading already uses the snake_case name:

if pagination.has_next_page:
    more_devices, _ = paginator.next_page(pagination.next_page_cursor)

So the heading named a property that does not exist in this SDK. This renames it to match, and updates the generated table of contents entry that references it.

Turned up while looking at camelCase identifiers in the SDK. Worth noting the API surface itself is consistent — every method and parameter is snake_case, since codegen converts the blueprint names. This was doc text that escaped that conversion.

uv run rstcheck README.rst passes, and the table of contents was regenerated with node generate-readme-toc.js rather than edited by hand.

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Generated by Claude Code