add cppcheck package (#10)

Cppcheck 2.19.1 static analysis tool, built from source. Includes
the MISRA C addon, cfg files, and platform definitions for opendbc
and panda safety analysis.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

cppcheck/build.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+set -e
+
+DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null && pwd)"
+cd "$DIR"
+
+VERSION="2.19.1"
+INSTALL_DIR="$DIR/cppcheck/install"
+
+# Idempotent: skip if already built
+if [ -x "$INSTALL_DIR/cppcheck" ]; then
+  echo "cppcheck already present, skipping build."
+  exit 0
+fi
+
+NJOBS="$(nproc 2>/dev/null || sysctl -n hw.ncpu 2>/dev/null || echo 2)"
+
+# Clone
+if [ ! -d "cppcheck-src" ]; then
+  git clone --depth 1 --branch "$VERSION" https://github.com/danmar/cppcheck.git cppcheck-src
+fi
+
+# Build
+cd cppcheck-src
+make MATCHCOMPILER=yes CXXFLAGS="-O2" -j"$NJOBS"
+cd "$DIR"
+
+# Install
+rm -rf "$INSTALL_DIR"
+mkdir -p "$INSTALL_DIR"
+
+cp cppcheck-src/cppcheck "$INSTALL_DIR/"
+cp -r cppcheck-src/addons "$INSTALL_DIR/"
+cp -r cppcheck-src/cfg "$INSTALL_DIR/"
+cp -r cppcheck-src/platforms "$INSTALL_DIR/"
+strip "$INSTALL_DIR/cppcheck" 2>/dev/null || true
+
+# Clean up
+rm -rf cppcheck-src
+
+echo "Installed cppcheck to $INSTALL_DIR"
+du -sh "$INSTALL_DIR"