Add OV9782 support, optional support for libcamera 0.6+, and add arm64 sysroot JNI build helper

[SoZ0]

Summary

This PR adds OV9782 support (C++ + Java), makes control-setting behave better across mono sensors and cameras that don’t expose certain controls, and includes a helper script for building/publishing an arm64 JNI against a sysroot (Docker by default). It also makes the libcamera>=0.6 requirement optional so we don’t break existing build environments.

What changed

• Add OV9782 camera model support in C++ and Java.
• Update model parsing (stringToModel) and treat OV7251 as grayscale.
• Make CameraGrabber::setControls check what controls the camera actually supports before setting them; handle mono sensors more cleanly.
• CMake: add REQUIRE_LIBCAMERA_0_6 (default OFF) to optionally enforce libcamera>=0.6.
• Build: make libcamera_meme optional (BUILD_CAMERA_MEME) and add tools/build_arm64_jni.sh for sysroot-based arm64 JNI builds.
• Docs + ignores: README updates and a couple .gitignore additions for local build/sysroot artifacts.

How to use

Enforce libcamera 0.6+ (only if you want it):

cmake -B cmake_build -S . -DREQUIRE_LIBCAMERA_0_6=ON

Arm64 sysroot JNI build:

SYSROOT_DIR=/path/to/target/rootfs \
  MAVEN_LOCAL_REPO=/path/to/m2 \
  tools/build_arm64_jni.sh

[mcm001]

I think for 2027+, we should force everyone to use a new libcamera?

[SoZ0]

Not sure what the over arching goals are, so I did not want to force 0.6 if there was other issues with other platforms. I would recommend it as 0.6+ is stable now to my knowledge

[thatcomputerguy0101]

Hopefully this fixes (unofficial) Debian/RPiOS Trixie support again. I don't have the time to check this today, but maybe tomorrow.

[mcm001]

Looks like we currently install libcamera 0.5.2 -> https://github.com/PhotonVision/photon-image-modifier/actions/runs/22130709321/job/64030036864?pr=126#step:5:1477

I think @Gold856 was partially through compiling libcamera from source as part of this driver build, which would release us from our dependence on random rpi apt repos.

[thatcomputerguy0101]

The RPiOS Trixie image has libcamera 0.6 preinstalled. While libcamera 0.5 is available, sufficiently removing 0.6 to install 0.5 is nontrivial.

[Gold856]

Yeah, I got libcamera 0.6 building completely independently. That's what I want to switch to for 2027. Still trying to work out how to ship the IPA files and stuff.

[mcm001]

Can you remind me why we should upstream this script, rather than the existing cross build setup? (Which granted only really works in CI or a real Pi)

[SoZ0]

Makes local dev much quicker and possible without access to direct hardware. I can swap it out with a full docker container so other environments can build easier or if its not wanted can be removed all together.

[mcm001]

I do think that the current cross-compiling story kinda sucks/isn't there, so I do see value in having a blessed way to build outside of the pipeline. I'll think a bit harder on it but that broadly makes sense to me