[mstan]

An active Gravity Well could capture Boss Rush bosses while their entrances used ordinary-enemy state and damage-category bytes, then dissolve or lift them into a false defeat. Check the Rush boss body's identity from allocation onward when selecting victims, validating retained captures, and supplying their renderer/AI override. Older snapshots containing an illegal boss capture release it safely. Ordinary minions sharing a boss's ownership tag remain eligible.

Adds a ROM-backed regression for normal/charged fields across all eight bosses in both seats, illegal-capture save/load, and deterministic entrance replay. Also adds an X3 Zero saber timing probe for campaign/Boss Rush and solo/local co-op: idle, repeated swings, real boss hits, and the full charge/two-buster/saber input chain, comparing diagnostics off/on after warming caches. The reported saber slowdown was not reproduced in these probes; this PR makes no speculative saber behavior change.

Validated on current main with its exact engine/UI/library pins:

• All 32 Gravity Well entrance cases: full boss HP, completed native entrances, zero false defeats.
• Illegal-capture load/release and byte-exact replay; ordinary X/Zero Gravity Well pull/lift/dissolve/charge/energy/replay, including ordinary enemies with boss ownership tags.
• Renderer, Zero, Boss Rush queue and current-main Boss Rush report CTest checks.
• All 28 distinct boss pairs in both Add Zero solo and fully registered local co-op: entrances, native weapon finishing hits, snapshot replay, replacements preserving the survivor, death/Retry/Main Menu.
• Saber scenarios complete with diagnostics off/on and byte-identical final game states in all four scene/player configurations. Real Boss Rush hits and the normal full-charge/two-buster/saber chain are verified.

Mean CPU time per game update plus compositor draw during the full X3 combo (768 frames per logging mode, warmed caches; this shared Windows host):

Scene	Players	Diagnostics off	Diagnostics on
Campaign	1	6.21 ms	6.19 ms
Campaign	2	6.83 ms	7.29 ms
Boss Rush	1	10.71 ms	10.79 ms
Boss Rush	2	11.39 ms	11.63 ms

Some individual frames spike with either logging setting. The affected user's replay and setup are still needed to identify their slowdown.

Tracking: beads-8wg.1.136.