3e19d2974e
SRD spells/mage-armor.md: 'An invisible but tangible field of force surrounds the subject of a mage armor spell, providing a +4 armor bonus to AC' - 'School conjuration (creation) [force]', level 1, 'Casting Time 1 standard action', 'Range touch', 'Duration 1 hour/level (D)', 'Spell Resistance no'. - data/spells/mage_armor.json: buff +4 armor to AC, 600 rounds (1 hour/level modeled fixed, the shield.json convention). Description documents the known simplification: the engine bakes worn armor into the AC total and cannot see it, so the armor bonus stacks additively with that baked value (two mage armors still do not stack). - effects.py: 'armor' added to BonusType; absent from _STACKING_TYPES it behaves as a keep-the-highest type (verified by resolve_modifiers tests). - Spell-count pins 107 -> 108 (test_runner_spells, batch3, test_spells) and the README references. - Golden transcript untouched (buff branch only fires when no offensive spell is selected; the lich still opens with Magic Missile).