fix: disk image build, piCore64 URL, license

- Add kpartx for reliable loop partition mapping in Docker containers
- Fix piCore64 download URL (changed from .img.gz to .zip format)
- Fix piCore64 boot partition mount (initramfs on p1, not p2)
- Fix tar --wildcards for RPi firmware extraction
- Add MIT license (same as KubeSolo)
- Add kpartx and unzip to Docker builder image

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

build/scripts/create-disk-image.sh

@@ -51,10 +51,39 @@ size=1048576, type=0FC63DAF-8483-4772-8E79-3D69D8477DE4, name="SystemB"
 type=0FC63DAF-8483-4772-8E79-3D69D8477DE4, name="Data"
 EOF
 
-# Set up loop device
-LOOP=$(losetup --show -fP "$IMG_OUTPUT")
+# Set up loop device with partition mappings
+LOOP=$(losetup --show -f "$IMG_OUTPUT")
 echo "==> Loop device: $LOOP"
 
+# Use kpartx for reliable partition device nodes (works in Docker/containers)
+USE_KPARTX=false
+if [ ! -b "${LOOP}p1" ]; then
+    if command -v kpartx >/dev/null 2>&1; then
+        kpartx -a "$LOOP"
+        USE_KPARTX=true
+        sleep 1
+        LOOP_NAME=$(basename "$LOOP")
+        P1="/dev/mapper/${LOOP_NAME}p1"
+        P2="/dev/mapper/${LOOP_NAME}p2"
+        P3="/dev/mapper/${LOOP_NAME}p3"
+        P4="/dev/mapper/${LOOP_NAME}p4"
+    else
+        # Retry with -P flag
+        losetup -d "$LOOP"
+        LOOP=$(losetup --show -fP "$IMG_OUTPUT")
+        sleep 1
+        P1="${LOOP}p1"
+        P2="${LOOP}p2"
+        P3="${LOOP}p3"
+        P4="${LOOP}p4"
+    fi
+else
+    P1="${LOOP}p1"
+    P2="${LOOP}p2"
+    P3="${LOOP}p3"
+    P4="${LOOP}p4"
+fi
+
 MNT_EFI=$(mktemp -d)
 MNT_SYSA=$(mktemp -d)
 MNT_SYSB=$(mktemp -d)
@@ -65,22 +94,25 @@ cleanup() {
     umount "$MNT_SYSA" 2>/dev/null || true
     umount "$MNT_SYSB" 2>/dev/null || true
     umount "$MNT_DATA" 2>/dev/null || true
+    if [ "$USE_KPARTX" = true ]; then
+        kpartx -d "$LOOP" 2>/dev/null || true
+    fi
     losetup -d "$LOOP" 2>/dev/null || true
     rm -rf "$MNT_EFI" "$MNT_SYSA" "$MNT_SYSB" "$MNT_DATA" 2>/dev/null || true
 }
 trap cleanup EXIT
 
 # Format partitions
-mkfs.vfat -F 32 -n KSOLOEFI "${LOOP}p1"
-mkfs.ext4 -q -L KSOLOA "${LOOP}p2"
-mkfs.ext4 -q -L KSOLOB "${LOOP}p3"
-mkfs.ext4 -q -L KSOLODATA "${LOOP}p4"
+mkfs.vfat -F 32 -n KSOLOEFI "$P1"
+mkfs.ext4 -q -L KSOLOA "$P2"
+mkfs.ext4 -q -L KSOLOB "$P3"
+mkfs.ext4 -q -L KSOLODATA "$P4"
 
 # Mount all partitions
-mount "${LOOP}p1" "$MNT_EFI"
-mount "${LOOP}p2" "$MNT_SYSA"
-mount "${LOOP}p3" "$MNT_SYSB"
-mount "${LOOP}p4" "$MNT_DATA"
+mount "$P1" "$MNT_EFI"
+mount "$P2" "$MNT_SYSA"
+mount "$P3" "$MNT_SYSB"
+mount "$P4" "$MNT_DATA"
 
 # --- EFI/Boot Partition ---
 echo "    Installing GRUB..."