fix(iso): fix linux-packages to "linux-image" so lb appends flavour correctly

live-build constructs the kernel package as <linux-packages>-<linux-flavours>,
so "linux-image-amd64" + "amd64" = "linux-image-amd64-amd64" (not found).
The correct value is "linux-image" + "amd64" = "linux-image-amd64".

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

iso/builder/auto/config

@@ -19,7 +19,7 @@ lb config noauto \
     --mirror-binary "https://deb.debian.org/debian" \
     --security true \
     --linux-flavours "amd64" \
-    --linux-packages "linux-image-amd64" \
+    --linux-packages "linux-image" \
     --memtest none \
     --iso-volume "EASY-BEE" \
     --iso-application "EASY-BEE" \