feedback1f WU: units on fenced tiles block no ground enemy (F4: 深巡 on a 围墙 tile attacks as usual)

F4 "干员深巡放在围栏围着的地块里不会主动攻击" is not reproduced: 深巡 (哨戒铁卫, range 2-2) attacks every
enemy on her range tiles from the fenced 围墙 tiles of every active stage, the Final Assault halves and
联防, through a real Match and in the browser's own battle. Locked by test/sim/feedback1f-fence.test.js.

Nearby rule fixed: PRTS 围墙 / 围栏 地形机制 "部署在其中的单位，若当前阻挡类型为'地面阻挡'则无法阻挡敌人".
A unit on a tile ground units cannot pass now blocks no ground enemy (Battle._blockerFor); before, an
enemy pushed or dragged to the fence edge (0.5 from the unit) was blocked there - 薄绿 S2 on a fenced
tile held the dragged enemies. Air blocking (blockFly against flyers) stays. Docs: SIM.md Blocking,
PLAYING.md tip on the fenced tiles.

docs/PLAYING.md

@@ -132,3 +132,4 @@
 - 进入隐秘核心看的是全队的**激活层数总和**：后期可以针对性地堆层数。
 - 层数到 999 就满了，多余的叠层没有用，可以把资源转去别的盟约。
 - 领袖战注意**限伤**：单次 30 万以上的伤害会被整次作废。盟约叠到 999 层后，再叠加额外的伤害倍率（例如 999 层谢拉格再点亮奥术）反而可能让大招打出 0 伤害；队友的奥术等减益也会放大你的伤害。
+- **橙色围栏围起的地块**（官方「围墙」）可以部署干员，敌人走不进去：站在里面的干员照常攻击自己攻击范围内的敌人（摆放时选好朝向，让攻击范围对着敌人走的路），但**挡不住地面敌人**（被推、拉到围栏边的敌人也不会被它阻挡），也很少挨打——重装干员（如深巡）的手动技能要受到伤害才释放，在里面可能一直不放；只打自己脚下一格的干员（如角峰）在里面打不到任何敌人。