fix: conversion HEIC — ajout fallback img+canvas pour Chrome macOS

src/lib/client/heicConverter.ts

@@ -46,15 +46,43 @@ export async function convertHeicToJpeg(blob: Blob): Promise<Blob> {
 }
 
 async function convertNative(blob: Blob): Promise<Blob> {
-  // Force le type MIME pour que le navigateur reconnaisse le format
   const typed = blob.type ? blob : new Blob([blob], { type: 'image/heic' })
-  const bitmap = await createImageBitmap(typed)
-  const canvas = document.createElement('canvas')
-  canvas.width = bitmap.width
-  canvas.height = bitmap.height
-  canvas.getContext('2d')!.drawImage(bitmap, 0, 0)
-  bitmap.close()
+
+  // Tentative 1 : createImageBitmap (Safari 14+)
+  try {
+    const bitmap = await createImageBitmap(typed)
+    const canvas = document.createElement('canvas')
+    canvas.width = bitmap.width
+    canvas.height = bitmap.height
+    canvas.getContext('2d')!.drawImage(bitmap, 0, 0)
+    bitmap.close()
+    return await canvasToBlob(canvas)
+  } catch {
+    // Pas supporté — essai suivant
+  }
+
+  // Tentative 2 : <img> + canvas (Chrome sur macOS — utilise le décodeur HEIC natif de macOS)
   return new Promise<Blob>((resolve, reject) => {
+    const url = URL.createObjectURL(typed)
+    const img = new Image()
+    img.onload = () => {
+      const canvas = document.createElement('canvas')
+      canvas.width = img.naturalWidth
+      canvas.height = img.naturalHeight
+      canvas.getContext('2d')!.drawImage(img, 0, 0)
+      URL.revokeObjectURL(url)
+      canvasToBlob(canvas).then(resolve).catch(reject)
+    }
+    img.onerror = () => {
+      URL.revokeObjectURL(url)
+      reject(new Error('Décodage HEIC non supporté par ce navigateur'))
+    }
+    img.src = url
+  })
+}
+
+function canvasToBlob(canvas: HTMLCanvasElement): Promise<Blob> {
+  return new Promise((resolve, reject) => {
     canvas.toBlob(
       b => (b ? resolve(b) : reject(new Error('canvas.toBlob a retourné null'))),
       'image/jpeg',