v0.10.3

Multi-browser cookie support, Linux, profile config, /google-account command.

Added

• /google-account command to report the active Google account for Gemini Web
• chromeProfile config for targeting a non-default Chromium profile
• searchModel config for overriding the Gemini API search model

Changed

• Cookie extraction now tries Helium, Chrome, and Arc on macOS; Chromium and Chrome on Linux
• Gemini Web availability checks pass required cookie names into extraction
• README covers Linux support, new config fields, and /google-account

Consolidates PRs #3, #5, #6, #8, #12. Thanks to @Whamp, @guilhermesilveira, @pepegar, @Zeng-Zer, and @lajarre.