fix(physics): port the Borland Real48 collision core

Add a bit-exact six-byte Real48 implementation for integer conversion,
rounding, comparison, add/subtract, multiply/divide, and Newton square root.
Use the normalized Borland random-register result and route speed clamps,
segment/circle detection, moving flippers, captures, triggers, and magnetic
fields through the recovered arithmetic instead of host floating formulas.

Preserve Real48 spin per ball and feed it through the original tangent/spin
response, separating zero-spin C fixtures from retained-spin Wine traces.
Replace path-progress selection with surface-distance ordering and implement
dynamic records 174/175, including impulse transfer to the other slot,
normal_velocity-1000 response, and the second post-collision speed clamp.

Test Plan:
- `cargo test --all-targets` -- passed, 69 tests
- `cargo clippy --all-targets -- -D warnings` -- passed
- `rumdl check tdkpin-rs/CHANGELOG.md tdkpin-rs/RECONSTRUCTION.md` -- passed
- `git diff --cached --check` -- passed

tdkpin-rs/CHANGELOG.md

@@ -10,6 +10,14 @@ and this project adheres to
 
 ### Fixed
 
+- Add a bit-exact Borland Real48 core and route speed clamps, type-1 circles,
+  type-2 segments, moving flippers, capture pulls, trigger randomization, and
+  magnetic impulses through its original rounding behavior.
+- Preserve per-ball Real48 spin and use it in collision tangent response, so
+  zero-spin C fixtures and retained-spin Wine traces are both represented.
+- Implement dynamic records 174/175 with bidirectional ball impulse transfer
+  and the original post-collision speed clamp instead of a one-sided secondary
+  bounce.
 - Split collision contact state into per-player 16-bit type-3 contact words and
   transient type-4 entry flags. Type-3 records now use the original deep-inside
   gate, `v*0.9 +/-150` pull, stationary sound/contact publication, 5-step age