feat(repair): inject ebike + pylon parts at packderelance anchors

- Ebike replacement parts: cooling core (correct, anchored at refroidisseur)
  + four distractors anchored at cabledroit/cablegauche/pucehaut/pucebas.
  Removes the ad-hoc gant_l/talkie distractors in favor of consistent
  case-anchored visuals.
- Pylon replacement parts: cable1 + cable2 (alternative correct, both with
  caseLockGroup 'pylon-cable' for upcoming soft-lock) + refroidisseur and
  two puce distractors anchored to packderelance.
- Farm replacement parts kept as-is (caseAnchor undefined falls back to
  placeholder slot positions for backward compatibility).
- RepairGame threads anchors from RepairCaseModel through RepairMissionCase
  to RepairRepairingStep; replacement-part initial position now resolves
  to the anchor world position when caseAnchor is set, falling back to the
  legacy slot index otherwise.

src/components/three/gameplay/RepairGame.tsx

@@ -1,7 +1,10 @@
 import { Suspense, useEffect, useMemo, useState } from "react";
 import { useGLTF } from "@react-three/drei";
 import { ExplodableModel } from "@/components/three/models/ExplodableModel";
-import type { RepairCasePlaceholder } from "@/components/three/gameplay/RepairCaseModel";
+import type {
+  RepairCasePartAnchors,
+  RepairCasePlaceholder,
+} from "@/components/three/gameplay/RepairCaseModel";
 import { RepairCompletionStep } from "@/components/three/gameplay/RepairCompletionStep";
 import { RepairInspectionObject } from "@/components/three/gameplay/RepairInspectionObject";
 import { RepairMissionCase } from "@/components/three/gameplay/RepairMissionCase";
@@ -63,6 +66,7 @@ export function RepairGame({
   const [casePlaceholders, setCasePlaceholders] = useState<
     readonly RepairCasePlaceholder[]
   >([]);
+  const [caseAnchors, setCaseAnchors] = useState<RepairCasePartAnchors>({});
   const [scannedBrokenParts, setScannedBrokenParts] = useState<
     readonly RepairScannedBrokenPart[]
   >([]);
@@ -81,6 +85,7 @@ export function RepairGame({
 
     const timeoutId = window.setTimeout(() => {
       setCasePlaceholders([]);
+      setCaseAnchors({});
       setScannedBrokenParts([]);
     }, 0);
 
@@ -137,6 +142,7 @@ export function RepairGame({
         ) : null}
         {step === "repairing" ? (
           <RepairRepairingStep
+            anchors={caseAnchors}
             brokenParts={scannedBrokenParts}
             config={config}
             placeholders={casePlaceholders}
@@ -159,6 +165,7 @@ export function RepairGame({
           <RepairMissionCase
             config={config}
             onPlaceholdersChange={setCasePlaceholders}
+            onAnchorsChange={setCaseAnchors}
             open={step === "repairing"}
             zoomed={step === "repairing"}
             showFragmentationPrompt={readyForFragmentation}