Sync canonical scaffolding, rename package and badge

[DaniusKalv]

Summary

• Adopt canonical build system across Makefile, setup.sh, dkms.conf, dkms.postinst and scripts
• Rename DKMS package from nv-ar0234 to ar0234-jetson-dkms, setup.sh purges old registration and sweeps its source tree
• Rename badge from 234M12 to interface form 234CSI in all four overlay spots
• Install ISP tuning per badge, kurokesu_front_234CSI.isp and kurokesu_rear_234CSI.isp, so each camera on a dual board resolves its own
• Bump to 0.3.0

On the dkms.conf diff

Gen-1 dkms.conf ran the entire build inline, generating Kbuild, calling conftest.sh and setting KBUILD_EXTRA_SYMBOLS plus nvidia-oot includes. Canonical moves all of that into the Makefile and leaves MAKE="make module KDIR=...", so the diff reads as a large deletion with nothing lost. It is the same recipe imx283, imx462 and imx585 already build with.

Test plan

• Run setup.sh on a target carrying the old package and confirm nv-ar0234 registration is removed, /usr/src/nv-ar0234-0.2.0 is swept, both tuning files are copied and a hand-placed camera_overrides.isp produces a RETIRE line
• Confirm dkms status reports only ar0234-jetson-dkms/0.3.0
• Reboot, confirm dmesg shows the sensor bound, then check streaming
• On dual setup, confirm each camera resolves its own badge file