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}

src/components/three/gameplay/RepairMissionCase.tsx

@@ -1,5 +1,6 @@
 import {
   RepairCaseModel,
+  type RepairCasePartAnchors,
   type RepairCasePlaceholder,
 } from "@/components/three/gameplay/RepairCaseModel";
 import { RepairPromptVideo } from "@/components/three/gameplay/RepairPromptVideo";
@@ -19,6 +20,7 @@ interface RepairMissionCaseProps {
   onPlaceholdersChange?:
     | ((placeholders: readonly RepairCasePlaceholder[]) => void)
     | undefined;
+  onAnchorsChange?: ((anchors: RepairCasePartAnchors) => void) | undefined;
   onExitComplete?: (() => void) | undefined;
   open?: boolean;
   zoomed?: boolean;
@@ -30,6 +32,7 @@ export function RepairMissionCase({
   config,
   exiting = false,
   onPlaceholdersChange,
+  onAnchorsChange,
   onExitComplete,
   open = false,
   zoomed = false,
@@ -57,6 +60,7 @@ export function RepairMissionCase({
             exiting={exiting}
             onExitComplete={onExitComplete}
             onPlaceholdersChange={onPlaceholdersChange}
+            onAnchorsChange={onAnchorsChange}
             open={open}
             floating={!zoomed}
             position={modelPosition}
@@ -70,6 +74,7 @@ export function RepairMissionCase({
           exiting={exiting}
           onExitComplete={onExitComplete}
           onPlaceholdersChange={onPlaceholdersChange}
+          onAnchorsChange={onAnchorsChange}
           open={open}
           floating={!zoomed}
           position={modelPosition}

src/components/three/gameplay/RepairRepairingStep.tsx

@@ -1,6 +1,9 @@
 import { useEffect, useRef, useState } from "react";
 import * as THREE from "three";
-import type { RepairCasePlaceholder } from "@/components/three/gameplay/RepairCaseModel";
+import type {
+  RepairCasePartAnchors,
+  RepairCasePlaceholder,
+} from "@/components/three/gameplay/RepairCaseModel";
 import { RepairObjectModel } from "@/components/three/gameplay/RepairObjectModel";
 import { RepairPromptVideo } from "@/components/three/gameplay/RepairPromptVideo";
 import { GrabbableObject } from "@/components/three/interaction/GrabbableObject";
@@ -38,6 +41,7 @@ const STORED_BROKEN_PART_COLOR = "#38bdf8";
 let hasWarnedMissingPlaceholders = false;
 
 interface RepairRepairingStepProps {
+  anchors?: RepairCasePartAnchors;
   brokenParts: readonly RepairScannedBrokenPart[];
   config: RepairMissionConfig;
   placeholders: readonly RepairCasePlaceholder[];
@@ -63,6 +67,7 @@ interface RepairPartPlacementFeedbackProps {
 }
 
 export function RepairRepairingStep({
+  anchors = {},
   brokenParts,
   config,
   placeholders,
@@ -193,7 +198,11 @@ export function RepairRepairingStep({
       <RepairPlaceholderMarkers positions={placeholderPositions} />
 
       {replacementParts.map((part, index) => {
+        const anchorPosition = part.caseAnchor
+          ? anchors[part.caseAnchor]
+          : undefined;
         const placeholderPosition =
+          anchorPosition ??
           placeholderPositions[index % placeholderPositions.length] ??
           placeholderPositions[0]!;
         const isPlaced = Boolean(placedPartIds[part.id]);