feat(feedback): add responsive camera and impacts

TODO.md

@@ -17,8 +17,8 @@ The largest gap between this and a AAA-feeling product is presentation, not code
 - [ ] **Audio — there is none.** Zero sound files, zero `AudioStreamPlayer` nodes, no bus layout. Needs: engine hum pitched to throttle, turbo whoosh, ball impacts scaled by collision impulse, wall scrapes, goal explosion, crowd bed, UI clicks, countdown beeps, music. Can be driven off `Ship`'s existing telemetry signals.
 - [x] SSAO/SSIL in the arena Environments — cheapest single perceived-quality win available; grounds the ships against the deck and gives the fillets and goal recesses real depth.
 - [x] VFX on anything that moves: throttle-reactive engine cores and plumes, distinct turbo flames, a speed-scaled ball trail, contact sparks and team-tinted goal bursts.
-- [ ] Impact feedback — screen shake, hit-stop, flash, controller rumble on ball contact.
-- [ ] Camera feel in `ship_camera.gd` — fixed distance/height/FOV today. Speed-based FOV widening, turbo kick, impact shake.
+- [x] Impact feedback — intensity-scaled screen shake, unscaled hit-stop, HUD flash and controller rumble on ball contact.
+- [x] Camera feel in `ship_camera.gd` — speed-based FOV widening, turbo kick-back and decaying impact shake.
 - [ ] Goal celebration sequence: today it's a `print()` and a label scale-pop. Wants an explosion, team-tinted screen flash, camera cut, slow-mo, title card. `HUDController`'s `ResultOverlay` animation is a reasonable template.
 - [x] Local lighting / dynamic GI — four local pitch lights plus SDFGI provide bounce and contact lighting for the runtime-generated arena shell; the shader's `hull_fill` stand-in is retired. (The shell is generated in `_ready`, so it cannot participate in an editor LightmapGI bake.)
 - [x] Dress `arena_03` — its asteroid field now has mining stations, debris clusters and a distant planet.