feat(docs): Explain supported feature combinations, add test script

feat-permut.sh

@@ -0,0 +1,69 @@
+#!/bin/bash
+## Build/ Test/ Clippy all supported feature permutations
+set -eu
+
+mode=${1:-help}
+wasm_target="--chrome --headless"
+extended=${2:-false}
+
+
+features_base=(
+  #cam,denm,uart
+  spat,gnss,screen
+)
+features_more=(
+  spat,gnss,screen,cam,denm
+)
+features_test=(
+  spat
+  spat,cam,denm
+)
+
+
+runBuild () {
+  for feat in "${features[@]}"; do
+    echo "cargo build for $feat ..."
+    cargo build --release --no-default-features -F esp,$feat
+  done
+}
+
+runTest () {
+  for feat in "${features_test[@]}"; do
+    echo "cargo test for $feat ..."
+    cargo test --target host-tuple --bin test --no-default-features -F std,$feat
+  done
+}
+
+runClippy () {
+  for feat in "${features[@]}"; do
+    echo "clippy for $feat ..."
+    cargo clippy --no-default-features -F esp,$feat -- -Wclippy::pedantic
+  done
+}
+
+if [ $extended == "--more" ]; then
+  echo "running with extended feature list"
+  features=( "${features_base[@]}" "${features_more[@]}" )
+else
+  echo "running standard feature list"
+  features=( "${features_base[@]}" )
+fi
+
+case $mode in
+build)
+  runBuild
+  ;;
+clippy)
+  runClippy
+  ;;
+test)
+  runTest
+  ;;
+all)
+  runBuild
+  runClippy
+  runTest
+  ;;
+*)
+  echo "Usage: $0 [build | clippy | test | all] [--more]"
+esac