fix(physics): restore slot-major timer batches

Freeze the active ball count at each detail callback, integrate every substep for slot one before slot two, and stop a slot after its first collision or lifecycle action. Effect-seven spawns are now deferred until the next callback, while a surviving slot two retains its original ball number for the remainder of a callback after slot one exits.

Test Plan:
- cargo test --all-targets
- cargo clippy --all-targets --all-features -- -D warnings
- rumdl check CHANGELOG.md RECONSTRUCTION.md README.md
- git diff --check

tdkpin-rs/CHANGELOG.md

@@ -10,6 +10,10 @@ and this project adheres to
 
 ### Fixed
 
+- Match the original detail callback's slot-major integration order, stop a
+  slot's remaining 10 ms substeps after its first collision/action, delay a
+  newly requested second ball until the next callback, and retain ball-two
+  identity while a captured/drained ball one is collapsed.
 - Run type-3 captures and type-4 triggers for both live ball slots, including
   per-slot capture age/contact ownership, exact captured-slot removal, survivor
   promotion, and the effect-seven ball-number guard against a third ball.