Fight SFX wave, second battle track, hero column refactor (3.4.2)

Fight playback now has sound. Seventeen cues are wired across the loop: turn start, turn end, phase banner, spell charge, hero spell, enemy spell, damage, heal, energy refill, KO, last resort, pickup, move, elemental strain, battle fatigue, win, lose. Field and playout-bar buttons also pick up the standard buttonClick SFX (groundwork landed May 7), so the field side of the loop is wired end-to-end now.

Fight music gained a second composition (`music_fight_2`), and the audio manager grew cycling-playlist support so battle scenes can rotate between tracks instead of looping a single one. Picks the next track when the current one ends; same crossfade behavior as the per-screen track selection that landed May 5.

The fight hero column got extracted into a dedicated `FightHeroSpellColumn` component with per-slot `HeroPanelLayout` overrides — same pattern as the HeroPanel system that rolled out in 2.1.3, applied now to the fight field. Native gap between hero panels tightened and action tags shrunk so a five-hero stack reads cleaner. Three new test files cover the column, slot derivers, and layout overrides.

Maya's first Heal sigil moved from Reaching Broken Temple to the end of Old Road, putting it earlier in Chapter 1 so players get hands on the effect-sigil mechanic sooner. The unlock dialogue and Heal-keyword routing all moved with it. Maya and Grey's character assets also got reorganized into per-folder layouts (`dialogue/`, `story/`, `field/`) — easier to find what you're looking for when adding new poses.