feedback5 O20: the 缚地 status (groundbind) — an enemy air unit counts as a ground unit and cannot move

ba.groundbind "目标变为地面单位，无法移动；使部分近地悬浮敌人掉落；对重量大于3的单位持续时间减半" (予愿安洁莉娜 S2 needs it):
- buffs.js: STATUS groundbind (flag groundbind + noMove, move x0), FLAG_KEYS, RESIST_STATUSES (as 束缚, [ASSUMED]);
- units.js isFlying: an enemy under 缚地 is a ground unit unless a 浮空 lifts it (same result as before without the flag);
- battle/status.js: 浮空 lands on a 缚地 data flyer (PRTS 异常效果 "…且不持有缚地异常…则Buff取消"), 缚地 halved on weight > 3;
- content/enemies: 掠海漂移体 / 吉兆飞鳞 drop on 缚地 as their PRTS text says (吉兆飞鳞 stays down while it holds);
- render/style.js: the 束缚 icon for it; docs/SIM.md (§2 isFlying, §3 flags / status table / 抵抗).
Nothing applies it yet: every golden family is unchanged. Test: test/sim/feedback5-groundbind.test.js.

public/js/render/style.js

@@ -122,7 +122,7 @@ export const PROJ = Object.freeze({
 export const STATUS_ICON = Object.freeze({
   stun: 'stun', freeze: 'freeze', cold: 'cold', stealth: 'stealth', shield: 'shield', fragile: 'fragile',
   artsFragile: 'fragile', physFragile: 'fragile', elemFragile: 'fragile', sleep: 'sleep', invulnerable: 'invuln',
-  silence: 'silence', slow: 'slow', sluggish: 'slow', bind: 'bind', fear: 'fear', tremble: 'fear', weaken: 'weaken',
+  silence: 'silence', slow: 'slow', sluggish: 'slow', bind: 'bind', groundbind: 'bind', fear: 'fear', tremble: 'fear', weaken: 'weaken',
   levitate: 'levitate', taunt: 'taunt', defDown: 'weaken', resDown: 'weaken', aspdDown: 'slow', disarm: 'silence',
   burn: 'burn', burnBurst: 'burn', neural: 'neural', neuralBurst: 'neural', necrosis: 'necrosis', apoptosis: 'necrosis',
   // a 傀儡师 fighting as its <替身> (sim professions.js buff 'trait:substitute', the 20 s form)