fix: resolve ShellCheck violations in shell scripts (#91)

- SC2155 (bin/localwp-setup.sh): declare local variables separately from
  command substitution assignments to avoid masking return values (13 fixes)
- SC2034 (bin/localwp-setup.sh): remove unused PLUGIN_TEXT_DOMAIN variable
- SC2162 (bin/localwp-setup.sh): add -r flag to read to avoid backslash mangling
- SC2154 (bin/setup-test-env.sh): add shellcheck disable for PHP variables in
  heredoc that ShellCheck incorrectly identifies as unassigned shell variables
- bin/setup-test-env.sh: remove self-modifying chmod +x $0 (unnecessary and
  bad practice; file permissions should be set once in version control)
- bin/setup-test-env.sh: change == to = in POSIX [ ] test expressions
- build.sh: add ./ prefix to directory glob copies for clarity
- build.sh: use subshell (cd build || exit 1; zip ...) instead of bare cd/cd..
  to avoid SC2103 and ensure working directory is always restored

Fixes part of #20 (shell script quality issues)

bin/localwp-setup.sh

@@ -28,7 +28,6 @@ set -e
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
 PLUGIN_SLUG="wp-plugin-starter-template"
-PLUGIN_TEXT_DOMAIN="wp-plugin-starter-template"
 
 # LocalWP paths (macOS)
 LOCAL_SITES_DIR="$HOME/Local Sites"
@@ -83,7 +82,8 @@ check_localwp() {
 		exit 1
 	fi
 
-    local version=$("$LOCAL_WP_CLI" --version 2>/dev/null || echo "unknown")
+	local version
+	version=$("$LOCAL_WP_CLI" --version 2>/dev/null || echo "unknown")
 	log_info "LocalWP WP-CLI version: $version"
 }
 
@@ -96,7 +96,8 @@ get_site_path() {
 # Get WordPress path within site
 get_wp_path() {
 	local site_name="$1"
-    local site_path=$(get_site_path "$site_name")
+	local site_path
+	site_path=$(get_site_path "$site_name")
 
 	# LocalWP uses app/public for WordPress files
 	echo "$site_path/app/public"
@@ -105,21 +106,24 @@ get_wp_path() {
 # Check if site exists
 site_exists() {
 	local site_name="$1"
-    local site_path=$(get_site_path "$site_name")
+	local site_path
+	site_path=$(get_site_path "$site_name")
 	[ -d "$site_path" ]
 }
 
 # Get plugin destination path
 get_plugin_path() {
 	local site_name="$1"
-    local wp_path=$(get_wp_path "$site_name")
+	local wp_path
+	wp_path=$(get_wp_path "$site_name")
 	echo "$wp_path/wp-content/plugins/$PLUGIN_SLUG"
 }
 
 # Sync plugin files to LocalWP site
 sync_plugin() {
 	local site_name="$1"
-    local plugin_dest=$(get_plugin_path "$site_name")
+	local plugin_dest
+	plugin_dest=$(get_plugin_path "$site_name")
 
 	if ! site_exists "$site_name"; then
 		log_error "Site '$site_name' does not exist"
@@ -181,7 +185,8 @@ create_site() {
 
 	check_localwp
 
-    local site_path=$(get_site_path "$site_name")
+	local site_path
+	site_path=$(get_site_path "$site_name")
 
 	if site_exists "$site_name"; then
 		log_warning "Site '$site_name' already exists at: $site_path"
@@ -230,7 +235,7 @@ create_site() {
 	echo ""
 
 	# Wait for user to create site
-    read -p "Press Enter after you've created the site in LocalWP..."
+	read -r -p "Press Enter after you've created the site in LocalWP..."
 
 	if site_exists "$site_name"; then
 		log_success "Site detected at: $site_path"
@@ -250,7 +255,8 @@ create_site() {
 # Install recommended plugins (matching Playground blueprint)
 install_recommended_plugins() {
 	local site_name="$1"
-    local wp_path=$(get_wp_path "$site_name")
+	local wp_path
+	wp_path=$(get_wp_path "$site_name")
 
 	log_info "Note: Install these plugins to match Playground environment:"
 	echo "  - Plugin Toggle (plugin-toggle)"
@@ -265,8 +271,10 @@ show_site_info() {
 	local domain="$2"
 	local multisite="$3"
 
-    local site_path=$(get_site_path "$site_name")
+	local site_path
-    local plugin_path=$(get_plugin_path "$site_name")
+	site_path=$(get_site_path "$site_name")
+	local plugin_path
+	plugin_path=$(get_plugin_path "$site_name")
 
 	echo ""
 	echo "============================================"
@@ -305,7 +313,8 @@ reset_site() {
 	echo
 
 	if [[ $REPLY =~ ^[Yy]$ ]]; then
-        local plugin_path=$(get_plugin_path "$site_name")
+		local plugin_path
+		plugin_path=$(get_plugin_path "$site_name")
 
 		log_info "Removing plugin files..."
 		rm -rf "$plugin_path"
@@ -345,14 +354,16 @@ show_info() {
 	echo "==============================="
 
 	for site_name in "$SINGLE_SITE_NAME" "$MULTISITE_NAME"; do
-        local site_path=$(get_site_path "$site_name")
+		local site_path
+		site_path=$(get_site_path "$site_name")
 
 		if site_exists "$site_name"; then
 			echo ""
 			echo "  ${GREEN}✓${NC} $site_name"
 			echo "    Path: $site_path"
 
-            local plugin_path=$(get_plugin_path "$site_name")
+			local plugin_path
+			plugin_path=$(get_plugin_path "$site_name")
 			if [ -d "$plugin_path" ]; then
 				echo "    Plugin: ${GREEN}Installed${NC}"
 			else

bin/setup-test-env.sh

@@ -1,8 +1,5 @@
 #!/bin/bash
 
-# Make this script executable
-chmod +x "$0"
-
 # Check if environment type is provided
 if [ -z "$1" ]; then
 	echo "Usage: $0 [single|multisite|playground-single|playground-multisite]"
@@ -49,7 +46,7 @@ install_wp_playground() {
 	fi
 }
 
-if [ "$ENV_TYPE" == "single" ]; then
+if [ "$ENV_TYPE" = "single" ]; then
 	echo "Setting up single site environment..."
 
 	# Install wp-env if needed
@@ -83,7 +80,7 @@ if [ "$ENV_TYPE" == "single" ]; then
 	echo "Site: http://localhost:8888"
 	echo "Admin login: admin / password"
 
-elif [ "$ENV_TYPE" == "multisite" ]; then
+elif [ "$ENV_TYPE" = "multisite" ]; then
 	echo "Setting up multisite environment..."
 
 	# Install wp-env if needed
@@ -124,7 +121,7 @@ elif [ "$ENV_TYPE" == "multisite" ]; then
 	echo "Test site: http://localhost:8888/testsite"
 	echo "Admin login: admin / password"
 
-elif [ "$ENV_TYPE" == "playground-single" ]; then
+elif [ "$ENV_TYPE" = "playground-single" ]; then
 	echo "Setting up WordPress Playground single site environment..."
 
 	# Install wp-playground if needed
@@ -193,7 +190,7 @@ EOF
 	echo "Admin login: admin / password"
 	echo "Press Ctrl+C to stop the server when done."
 
-elif [ "$ENV_TYPE" == "playground-multisite" ]; then
+elif [ "$ENV_TYPE" = "playground-multisite" ]; then
 	echo "Setting up WordPress Playground multisite environment..."
 
 	# Install wp-playground if needed
@@ -205,6 +202,7 @@ elif [ "$ENV_TYPE" == "playground-multisite" ]; then
 	zip -r dist/plugin.zip . -x "node_modules/*" "dist/*" ".git/*"
 
 	# Update blueprint to use local plugin
+	# shellcheck disable=SC2154
 	cat >playground/multisite-blueprint.json <<EOF
 {
   "landingPage": "/wp-admin/network/",

build.sh

@@ -46,9 +46,9 @@ cp -R README.md LICENSE CHANGELOG.md readme.txt composer.json "$BUILD_DIR/"
 # Copy directories
 echo "Copying directories..."
 mkdir -p "$BUILD_DIR/admin" "$BUILD_DIR/includes" "$BUILD_DIR/languages" "$BUILD_DIR/assets"
-cp -R admin/* "$BUILD_DIR/admin/"
+cp -R ./admin/* "$BUILD_DIR/admin/"
-cp -R includes/* "$BUILD_DIR/includes/"
+cp -R ./includes/* "$BUILD_DIR/includes/"
-cp -R languages/* "$BUILD_DIR/languages/"
+cp -R ./languages/* "$BUILD_DIR/languages/"
 
 # Create assets directory structure
 mkdir -p "$BUILD_DIR/assets/banner" "$BUILD_DIR/assets/icon" "$BUILD_DIR/assets/screenshots"
@@ -73,9 +73,10 @@ fi
 
 # Create ZIP file.
 echo "Creating ZIP file..."
+(
 	cd build || exit 1
 	zip -r "../$ZIP_FILE" "$PLUGIN_SLUG" -x "*.DS_Store" -x "*.git*" -x "*.github*"
-cd ..
+)
 
 # Check if ZIP file was created successfully
 if [ -f "$ZIP_FILE" ]; then