要塞分支不再攻击空中单位；莫斯提马的减速显示状态图标 (#48)

要塞分支（灰毫 chess_char_2_18、号角 chess_char_5_08，普通与精锐）按官方不能攻击空中单位：build-data 不再把 fortress 归为可对空，重新生成 data/chess.json（只改这 4 条记录的 canHitFly），DESIGN §21.29 的技能释放调整保持不变。莫斯提马天赋的减速补上可见的减速状态图标（减速本身 0.1.1 已生效）。fix #35

docs/SIM.md

@@ -1074,7 +1074,7 @@ table: `hitSleep` (targets and damages sleeping enemies — "可以攻击沉睡
 | bard | no attack; every second heals allies in range 10 % ATK (bb atk_to_hp_recovery_ratio) |
 | craftsman | melee phys (support devices via kit) |
 | shotprotector | ranged phys, can hit FLY, blocks 3 |
-| fortress | melee single target while blocking, ranged 1.0 splash otherwise |
+| fortress | melee single target while blocking, ranged 1.0 splash otherwise, ground only (never hits FLY) |
 | unyield / musha / reaper | cannot be healed by others; musha heals itself 50 (bb value) per hit; reaper hits every enemy in range and heals 50 × min(hits, block) |
 | centurion / crusher / pusher | hit every blocked enemy at once |
 | hammer | 50 % splash (bb atk_scale_2) to others within 1 tile |