feedback7 R22-GHSIM: 假想敌：骨刺 changes model with its 隐匿 at once — the three-headed snake (*_A) while hidden, its *_B set when blocked or revealed, back to *_A when hidden again (GitHub #296, PR #365 by @Sukvii, render part); golden: unchanged

The contributor's code (render/spine.js syncFormPose, the render/units.js wiring and FORMS entry, the headless
test/render/forms.test.js block), applied from PR #365, so they are the author of this commit. Maintainer side: the
hard-coded Spine id became a STEALTH_FORMS table (form while the stealth bit is off), comments and docs/ASSETS.md
reworded. Not ported: the PR's sim targeting rewrite (content/enemies/invisible.js), its enemies_bosses tests, its
roster.json and the Chrome suite (forms.browser.test.js, not run here).

Seen (#296, FrogThai): a blocked 骨刺 kept the snake. The sim already sends UF.STEALTH only while its 隐匿 is effective
(not blocked, not revealed — targeting.js enemyStealthed); the view now keys the FORMS 'revealed' clip set (Idle_B /
Move_B / Die_B / Attack_B, all in the skeleton) off that bit in UnitView.sync — before a DIE of the same snapshot — and
re-poses at once: a running attack continues in the other attack clip at the same point relative to its strike frame
(Attack_A hit 0.533 s, Attack_B 0.733 s; a pending wind-up still strikes on time), a stun / idle restarts on the new set
without a crossfade, and a frozen skeleton is posed with update(0); a model loaded later is posed the same way.
Golden: unchanged (render only).

docs/ASSETS.md

@@ -273,8 +273,12 @@ catch-up frames and hidden tabs (`keepsState`), the game screen's pre-entry buff
 event queue (`render/interp.js isCosmeticEvent`) too — or, for a view built mid-battle, UnitInfo `form`, which `render/app/info.js renderInfo` passes to the view; a
 `change` clip plays once first, an `end` clip is timed from the fx's `dur` to finish as that state ends, keeping the
 current form's death clip until the next form's fx). A blocked or revealed 隐匿 enemy is drawn solid: the sim sends the
-stealth bit only while its 隐匿 is on:
+stealth bit only while its 隐匿 is on — and 假想敌：骨刺 changes model with that bit, not with an fx (`STEALTH_FORMS`, GitHub
+#296, PR #365): the manifest's `*_A` (the three-headed snake) while the bit is on, its `*_B` set (form `revealed`) the
+moment it is blocked or revealed, `*_A` again when its 隐匿 is back; no change clip, a running attack, stun or freeze
+pose carried over (`render/spine.js syncFormPose`). The forms:
 - 掠海漂移体's crawl (`Change`, then `*_02`);
+- 假想敌：骨刺 (`*_A` / `*_B`, above);
 - 转译基底·α's three forms (`A_Die_B` / `_C` / `_D`, 2 s each, then `B_*` 寻仇者, `C_*` 幽灵, `D_*` 特战术师);
 - the 深池逐火 embers (`Die`, then `Idle_2` / `Move_2` / `Die_2`; `Revive` ends as it stands up) and 假想敌：再生's puppet
   (`A_Die`, then `B_*`; `B_Revive`);