docs: update README to reflect current feature status

docs: add website link to README

fix: cross-platform AI agent detection for macOS and Linux servers

feat: restore and update screenshot UI tests for multi-agent tabs

refactor: unify AI agent tab switching with fixed-width tabs

feat: add AI agent brand icons and plugin architecture

feat: AI Agent Plugin Architecture with Claude + OpenCode support

fix: WhisperKit model loading and voice input preview guard

fix: position toolbar above home indicator when keyboard is hidden

fix: resolve keyboard dismiss not resizing terminal in mosh sessions

fix: handle Ctrl+key combos via UIKeyCommand for reliable tmux keybindings

fix: stop LiveDot animation from causing history page to blink on Mac

docs: add Phase 6 (Claude Code support) to plan.md

feat: add Claude Code session management with tabbed browser

feat(settings): split app and terminal themes