`place="bottom"` ignored --material-bottom-bar, so a floating toolbar overlapped
the shell's navigation bar and a docked one landed squarely on it. Both now clear
it — max(), not a sum, since that height already swallows the bottom safe area —
and the docs say what M3 says: never show a docked toolbar and a navigation bar
together. Plan: docs/plans/material-3-alignment.md, step 14 (navigation N-02).
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9
