feat(boards/modalai/voxl2): add Debian packaging framework

Add a scalable .deb packaging framework for VOXL2, built on the
existing cmake/package.cmake CPack infrastructure. The framework
handles multi-processor boards by having the POSIX (_default) build
own the .deb and pull in the companion SLPI build's artifacts.

Board-specific files:
- cmake/package.cmake: CPack variable overrides (name, deps, version)
- cmake/install.cmake: install() rules for all .deb contents
- debian/postinst: px4-* symlinks, DSP signature, directory setup
- debian/prerm: service stop, symlink cleanup
- debian/voxl-px4.service: systemd unit (after sscrpcd)

Infrastructure changes:
- cmake/package.cmake: hook for board-specific CPack overrides
- platforms/posix/CMakeLists.txt: hook for board install.cmake
- Makefile: %_deb pattern rule (build _default, then cpack -G DEB)
- CI: auto-discover _deb targets, collect .deb artifacts, upload
  to GitHub Releases

Future boards: add cmake/package.cmake + cmake/install.cmake and
CI discovers it automatically. No new file formats or tools needed.

Signed-off-by: Ramon Roche <mrpollo@gmail.com>

Tools/ci/generate_board_targets_json.py

@@ -207,6 +207,47 @@ for manufacturer in sorted(os.scandir(os.path.join(source_dir, '../boards')), ke
                         if t not in companions
                     ]
 
+# Append _deb targets for boards that have cmake/package.cmake
+for manufacturer in sorted(os.scandir(os.path.join(source_dir, '../boards')), key=lambda e: e.name):
+    if not manufacturer.is_dir():
+        continue
+    if manufacturer.name in excluded_manufacturers:
+        continue
+    for board in sorted(os.scandir(manufacturer.path), key=lambda e: e.name):
+        if not board.is_dir():
+            continue
+        board_name = manufacturer.name + '_' + board.name
+        if board_name in excluded_boards:
+            continue
+        package_cmake = os.path.join(board.path, 'cmake', 'package.cmake')
+        if os.path.exists(package_cmake):
+            deb_target = board_name + '_deb'
+            if target_filter and not any(deb_target.startswith(f) for f in target_filter):
+                continue
+            # Determine the container and group for this board
+            container = default_container
+            if board_name in board_container_overrides:
+                container = board_container_overrides[board_name]
+            target_entry = {'target': deb_target, 'container': container}
+            if args.group:
+                # Find the group where this board's _default target already lives
+                default_target = board_name + '_default'
+                group = None
+                for g in grouped_targets:
+                    targets_in_group = grouped_targets[g].get('manufacturers', {}).get(manufacturer.name, [])
+                    if default_target in targets_in_group:
+                        group = g
+                        break
+                if group is None:
+                    group = 'base'
+                target_entry['arch'] = group
+                if group not in grouped_targets:
+                    grouped_targets[group] = {'container': container, 'manufacturers': {}}
+                if manufacturer.name not in grouped_targets[group]['manufacturers']:
+                    grouped_targets[group]['manufacturers'][manufacturer.name] = []
+                grouped_targets[group]['manufacturers'][manufacturer.name].append(deb_target)
+            build_configs.append(target_entry)
+
 if(verbose):
     import pprint
     print("============================")

Tools/ci/package_build_artifacts.sh

@@ -3,6 +3,7 @@
 mkdir artifacts
 cp **/**/*.px4 artifacts/ 2>/dev/null || true
 cp **/**/*.elf artifacts/ 2>/dev/null || true
+cp **/**/*.deb artifacts/ 2>/dev/null || true
 for build_dir_path in build/*/ ; do
   build_dir_path=${build_dir_path::${#build_dir_path}-1}
   build_dir=${build_dir_path#*/}