0.34.0

A launch with an explicit userDataDir keeps session cookies (cookies without an expiry date, which most logins set) across a normal close() and relaunch (issue #187). Before, Chromium deleted them on every clean start, so a persistent profile lost its logins. The browser's own encrypted cookie store keeps them: Chromium launches with --restore-last-session, and the last session's tabs are dropped first so the launch still starts with one tab (restoreTabs: true reopens them). Firefox under the selenium engine starts with browser.startup.page=3 and the restored tabs are closed. The Playwright engine launches the full Chromium build headless (channel: 'chromium'), because the headless shell cannot keep session cookies. Safari, an attached browser, and an explicitly selected headless shell return a keepSessionCookies warning in warnings.

Every entry point supports it: launchBrowser with any engine and launch mode, connectOrLaunch, launchRealBrowser, launchWebDriver, and the CLI (--keep-session-cookies, --no-keep-session-cookies, --restore-tabs). keepSessionCookies: false opts out, and temporary profiles behave as before. Launch results report keepSessionCookies and warnings. New exports: persistentProfileArgs(), clearRestoredTabs(), KEEP_SESSION_COOKIES_SWITCH, FIREFOX_KEEP_SESSION_COOKIES_PREFERENCES and SESSION_RESTORE_FILES.

Related Pull Request: #188

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