feedback1 WD: late views keep the form in the client, 重生 clears statuses, blocked 隐匿 drawn solid

- render/app.js: the views' unit info is built by the exported renderInfo(UnitInfo), which now keeps `form`;
  addInfo dropped it, so a view built from fieldMeta (a teammate's field watched later, 联防 observers, a
  reconnect) still drew the first form. Tested through renderInfo (fake PIXI) and the real enterBattle(meta)
  path in headless Chrome (opt-in).
- content/enemies.js: rebirthCleanse at every 重生 (reborn, husk, statue): operator-applied buffs and
  source-less statuses go, own talents / enemy-given buffs / field state stay (PRTS 特殊机制 §重生). A 逐火
  knocked out while feared is no longer an unblockable ember.
- snapshot.js: an enemy's stealth bit only while its 隐匿 is on (not blocked, not revealed).
- Docs: area damage reaching an unblocked 隐匿 enemy is documented as an engine deviation (PRTS 作战机制
  §AOE伤害判定), not as the rule.

public/js/render/units.js

@@ -27,7 +27,7 @@
 // Enemy modes (sim fx 'phase' { id, kind } or another fx's `form` → `setForm(kind, fx)`): 掠海漂移体 dropping to 爬行模式
 // (user playtest #5 item 1) plays its skeleton's 'Change' clip once, then the crawl set (*_02); 转译基底's forms, the 逐火
 // embers, 再生's puppet, the leaders' 重生 and 守墓石像 likewise (user report after 0.1.0) — FORMS. A view built later
-// (UnitInfo `form`, the sim's current form) starts in the mode.
+// (`info.form` = UnitInfo `form`, the sim's current form, through render/app.js renderInfo) starts in the mode.
 // Element gauges (b.snap `elem` → sample `el` / `elFill` / `elUntil` / `elDur`), the official form (PRTS 元素: "模型
 // 下部会显示对应的元素图标，并以白条显示剩余的元素值"; enemies "小尺寸图标（不显示元素图标，仅根据元素种类改变背景色）"): a row
 // right under the unit's own HP / SP bars and inside their span — the element's disc at the left (operators with its