fix(physics): restore fixed-point rail movement

Replace the guessed variable-rate floating integration with the original 10 ms
millipixel step, 15-unit gravity, and 3800-unit speed limit. Restore every
registered type-2 Real48 response pair, one-sided start-to-end orientation, and
the original normal/tangent velocity transform validated against live shooter
wall traces.

Restore repeat-driven plunger charging and its release-time randomized clamp.
The shooter route now follows table orientation instead of coordinate-specific
gate exceptions. Remove the synthetic ball-search impulse so future stuck balls
remain visible reconstruction failures, and include collision ids in deterministic
traces for differential work on circles and triggers.

Test Plan:
- `cargo test --all-targets` -- 42 passed
- `cargo clippy --all-targets -- -D warnings` -- passed
- `cargo build --profile production` -- passed
- charged launcher scenario cleared the shooter lane -- passed
- all recovered rails accepted front-side and rejected back-side probes
- `git diff --cached --check` -- passed

tdkpin-rs/RECONSTRUCTION.md

@@ -22,10 +22,10 @@ implementation.
 | Artwork | Exact | All 34 custom DIB images, three standard bitmaps, icon, and palette derivatives are preserved in `assets/original/`. The game uses the original 640x460 table, loading, help, ball, wheel, robot, plunger, media, and diamond frames. |
 | Audio | Exact samples | All 16 mono PCM WAV resources are embedded unchanged. Their trigger roles were recovered from resource use and gameplay context. |
 | Help and languages | Exact | Original resource images 1001-1005 are displayed directly. |
-| Playfield collision layout | Recovered | All 109 active type-2 line objects and 40 static active type-1 circles are transcribed from the original 175-object registration table. The registration routine converts its sideways inputs with `screen = (y, x - 20)` and accumulates explicitly relative objects. Its circle sizes are complete center-contact extents, so the rendered ball radius is not added a second time. Object 174 is omitted because the original overwrites it with the live ball every frame. Moving flippers use equivalent native Rust bodies. |
-| Ball launcher | Recovered | The initial 32-bit fixed-point coordinates decode to `(325, 413)` in the right shooter lane. Scan code `0x50` compresses the eleven frames in resource 901 while Down is held; the key-release routine activates the ball with the accumulated vertical launch velocity. |
-| Physics arithmetic | Reimplemented | The Win16 fixed-point/timer engine is replaced by deterministic fixed-step floating-point integration. Restitution and impulses are tuned to the recovered table but are not instruction-for-instruction equivalents. |
-| Rules | Partly recovered | Player count, controls, wheel holes, magnetic saves, four-position ball lock, target banks, increasing bumper value, nine-part TDK diamond, permanent double scoring for a completed diamond, KByte media progression, and media extra balls follow the original help and code paths. The claw state machine has now been recovered in readable form, but its raw release-coordinate projection is still being decoded before the Rust behavior can claim parity. |
+| Playfield collision layout | Recovered | All 109 active type-2 line objects and 40 static active type-1 circles are transcribed from the original 175-object registration table. The registration routine converts its sideways inputs with `screen = (y, x - 20)` and accumulates explicitly relative objects. Type-2 records now retain every recovered Real48 normal/tangent response pair and their registered one-sided orientation. Circle sizes are complete center-contact extents, so the rendered ball radius is not added a second time. Object 174 is omitted because the original overwrites it with the live ball every frame. Moving flippers remain pending exact integration. |
+| Ball launcher | Recovered | The initial 32-bit fixed-point coordinates decode to `(325, 413)` in the right shooter lane. The port reproduces the initial `-375` millipixel Down event, 650 ms repeat delay, 40 ms repeats, release impulse, and randomized clamp below the original `-3800` maximum. This replaces the former guessed 330-430 px/s shot. |
+| Physics arithmetic | Partly recovered | Production movement uses the original 10 ms millipixel substep, `+15` vertical acceleration, `3800` speed bound, point-path type-2 intersection, one-sided line orientation, and Real48 normal/tangent response. Type-1 circles, type-3/4 triggers, collision-contact bookkeeping, and flipper impulses still use or coexist with floating reimplementations and remain pending. |
+| Rules | Partly recovered | Player count, controls, wheel holes, magnetic saves, four-position ball lock, target banks, increasing bumper value, nine-part TDK diamond, permanent double scoring for a completed diamond, KByte media progression, and media extra balls follow the original help and code paths. The claw state machine and release table are readable and terminal 18 has live differential evidence; terminals 1, 6, and 7 still need equivalent live coverage. |
 | Numeric scoring | Partly inferred | Visible 2000-6000 target values and recovered registration values are preserved. Some bumper, bank-completion, robot, wheel, lock, and media thresholds are best-evidence reconstructions because the decompiler did not recover meaningful names or a clean rule table. |
 | High scores | Compatible import | The original 276-byte table is decoded as ten `IWIK`-XOR-obfuscated little-endian scores plus ten 22-byte names, sorted, then migrated to portable JSON. |
 | Configuration | Behaviorally compatible | Sound, language, and five detail levels are retained. Storage moves from a local Win16 INI file to the platform user-data directory. |
@@ -58,14 +58,14 @@ decoded, build-ready subset; it does not replace that evidence archive.
   backend, the attract screen was inspected, a game was started, a ball was
   launched, collision scoring was observed, and a rendered frame was captured.
 - Original-runtime comparison: Wine 11.15 staging ran the preserved Win16 NE
-  executable; keypad `+`, a 1.1-second Down hold, release, and the resulting
-  launch were captured and compared with deterministic Rust states. A chosen
-  original claw terminal was not forced live, so claw evidence is static code,
-  decoded numeric constants, original assets, and Rust state/frame traces.
+  executable. Live millipixel traces cover keypad `+`, repeat-driven charging,
+  release, the shooter route, ordinary rail responses, and a controlled
+  terminal-18 claw capture and release. The line solver has unit tests against
+  exact outer/inner shooter-wall states from those traces.
 - Deterministic mechanics coverage: named launcher, flipper, and all four claw
-  terminal scenarios advance at exact 120 Hz steps, record JSON state/event
-  traces, and can export the logical 640x460 render target at any requested
-  step for visual inspection.
+  terminal scenarios are driven by a 120 Hz validation clock while production
+  physics accumulates the recovered 100 Hz substep. Traces include the last
+  collision-object id and can export the logical 640x460 render target.
 - Semantic boundary: no claim is made that every trajectory or score tick is
   bit-identical to the 16-bit executable. Remaining numeric inference is listed
   above instead of being presented as proven parity.
@@ -76,5 +76,6 @@ decoded, build-ready subset; it does not replace that evidence archive.
 - `assets.rs`: compile-time original asset embedding;
 - `game.rs`: fixed-step game state, recovered walls, rules, and scoring;
 - `geometry.rs`: segment/circle collision primitives;
+- `original_physics.rs`: millipixel integration and recovered type-2 responses;
 - `table.rs`: source-traceable collision objects recovered from the Win16 table;
 - `persistence.rs`: platform paths, settings, high scores, and legacy import.