why

We made a change to browser.close behavior, but the docs didn't contain the changes yet. This PR updates the docs to match existing close patterns

what changed

Docs are updated to match current behavior

test plan

just docs and review the changes live

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Summary by cubic

Updates the docs to match the current browser.close() behavior, where calling it ends the session even with keep-alive enabled. To keep a session alive for later reconnection, you now close only the Stagehand runtime and skip browser.close().

• Updates the keep-alive section in the browser configuration docs with the new closing patterns for TypeScript, Python, and Go.
• Revises the Browserbase and local environment behavior tables, the migration guides, and the Python SDK README to match the new behavior.