build: remove testing.sh in favor of runit.sh; add claude.md reference

Replace inline boot testing with standalone runit.sh runner for clarity:
- Remove scripts/lib/testing.sh source and boot_tests stage from build.sh
- Remove --skip-tests option from build.sh and rebuild-after-zinit.sh
- Update all docs to reference runit.sh for QEMU/cloud-hypervisor testing
- Add comprehensive claude.md as AI assistant entry point with guidelines

Testing is now fully decoupled from build pipeline; use ./runit.sh for
QEMU/cloud-hypervisor validation after builds complete.

scripts/build.sh

@@ -15,7 +15,6 @@ source "${SCRIPT_DIR}/lib/alpine.sh"
 source "${SCRIPT_DIR}/lib/components.sh"
 source "${SCRIPT_DIR}/lib/initramfs.sh"
 source "${SCRIPT_DIR}/lib/kernel.sh"
-source "${SCRIPT_DIR}/lib/testing.sh"
 
 # Build configuration loaded from config/build.conf via common.sh
 # Environment variables can override config file values
@@ -42,7 +41,6 @@ ZINIT_CONFIG_DIR="${CONFIG_DIR}/zinit"
 # Build options
 USE_CONTAINER="${USE_CONTAINER:-auto}"
 CLEAN_BUILD="${CLEAN_BUILD:-false}"
-SKIP_TESTS="${SKIP_TESTS:-false}"
 KEEP_ARTIFACTS="${KEEP_ARTIFACTS:-false}"
 
 # Display usage information
@@ -54,7 +52,6 @@ Usage: $0 [OPTIONS]
 
 Options:
   --clean              Clean build (remove all artifacts first)
-  --skip-tests         Skip boot tests
   --keep-artifacts     Keep build artifacts after completion
   --force-rebuild      Force rebuild all stages (ignore completion markers)
   --rebuild-from=STAGE Force rebuild from specific stage onward
@@ -92,10 +89,6 @@ function parse_arguments() {
                 CLEAN_BUILD="true"
                 shift
                 ;;
-            --skip-tests)
-                SKIP_TESTS="true"
-                shift
-                ;;
             --keep-artifacts)
                 KEEP_ARTIFACTS="true"
                 shift
@@ -411,18 +404,9 @@ function main_build_process() {
         kernel_build_with_initramfs "$KERNEL_CONFIG" "$INITRAMFS_ARCHIVE" "$kernel_output"
         export KERNEL_OUTPUT="$kernel_output"
     }
-    
-    function stage_boot_tests() {
-        if [[ "$SKIP_TESTS" != "true" ]]; then
-            # Ensure KERNEL_OUTPUT is set (for incremental builds)
-            if [[ -z "${KERNEL_OUTPUT:-}" ]]; then
-                KERNEL_OUTPUT="${DIST_DIR}/vmlinuz.efi"
-                export KERNEL_OUTPUT
-            fi
-            testing_run_all "$KERNEL_OUTPUT"
-        fi
-    }
-    
+
+    # Boot tests removed - use runit.sh for testing instead
+
     # Run all stages with incremental tracking
     stage_run "alpine_extract" stage_alpine_extract
     stage_run "alpine_configure" stage_alpine_configure
@@ -442,8 +426,7 @@ function main_build_process() {
     stage_run "initramfs_create" stage_initramfs_create
     stage_run "initramfs_test" stage_initramfs_test
     stage_run "kernel_build" stage_kernel_build
-    stage_run "boot_tests" stage_boot_tests
-    
+
     # Calculate build time
     local end_time=$(date +%s)
     local build_time=$((end_time - start_time))
@@ -501,16 +484,13 @@ function main() {
         log_info "Starting container build"
         docker_detect_runtime
         docker_build_container
-        
+
         # Pass through relevant arguments to container
         local container_args=""
-        if [[ "$SKIP_TESTS" == "true" ]]; then
-            container_args="$container_args --skip-tests"
-        fi
         if [[ "$KEEP_ARTIFACTS" == "true" ]]; then
             container_args="$container_args --keep-artifacts"
         fi
-        
+
         docker_run_build "./scripts/build.sh${container_args}"
     else
         log_error "Container runtime required (podman or docker)"