feedback1 WD: form changes survive the client's catch-up frames, hidden tab and pre-entry buffer

Every setForm fx now carries 'form' (shared/protocol.js fxForm). The runner keeps
these fx in catch-up frames (keepsState), holds the state-bearing events of the
battle on screen while the tab is hidden and delivers them with the first frame
back (re-entering from the field meta past HELD_MAX); screens/game.js buffers
them before a field is entered. A husk beaten while its stand-up clip plays dies
on the husk's clip. 幽灵 form cited from PRTS; 特战术师 flyer question recorded.

docs/ASSETS.md

@@ -203,11 +203,12 @@ A skill clip may also come from directional-only animations when a model has no
 The resolver's full precedence list is in the header of `tools/assets/anim-roles.mjs`.
 
 The manifest roles describe an enemy's first form. Enemies whose skeleton holds another form's clip set get it from
-`public/js/render/units.js FORMS` (keyed by Spine id, switched by the sim's 'phase' fx kind or the `form` of its
-'ember' / 'revive' / 'telegraph' / 'stone' fx — or, for a view built mid-battle, UnitInfo `form`, which
-`render/app.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). A blocked or revealed 隐匿 enemy is drawn solid: the sim sends the stealth bit only
-while its 隐匿 is on:
+`public/js/render/units.js FORMS` (keyed by Spine id, switched by the `form` of the sim's 'phase' / 'ember' / 'revive'
+/ 'telegraph' / 'stone' fx — `shared/protocol.js fxForm`; the client runner keeps these fx through catch-up frames and
+hidden tabs — or, for a view built mid-battle, UnitInfo `form`, which `render/app.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:
 - 掠海漂移体's crawl (`Change`, then `*_02`);
 - 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