All public types, fields, and functions in game.rs and map_file.rs now
have /// doc comments. main.rs has /// on App and draw_glyph plus inline
comments explaining the input/render pipeline. CLAUDE.md records the
expectation that generated code includes comments.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Introduces a map file format: TOML with a [palette] mapping characters
to (Glyph, Element) definitions and a [grid] multi-line string. Board
now owns the player position, objects, and portals. map_file::load()
deserializes a file and converts it to a Board via From<MapFile>.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>