feat: add --packs flag for custom pack selection

Users can now install specific packs with --packs=peon,glados,peasant.
The pack picker on peonping.com generates this command. Backward
compatible: bare curl|bash still installs the 10 defaults.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: garysheng

install.sh

@@ -6,10 +6,12 @@ set -euo pipefail
 
 LOCAL_MODE=false
 INSTALL_ALL=false
+CUSTOM_PACKS=""
 for arg in "$@"; do
   case "$arg" in
     --local) LOCAL_MODE=true ;;
     --all) INSTALL_ALL=true ;;
+    --packs=*) CUSTOM_PACKS="${arg#--packs=}" ;;
   esac
 done
 
@@ -184,7 +186,10 @@ else
 fi
 
 # Select packs to install
-if [ "$INSTALL_ALL" = true ]; then
+if [ -n "$CUSTOM_PACKS" ]; then
+  PACKS=$(echo "$CUSTOM_PACKS" | tr ',' ' ')
+  echo "Installing custom packs: $PACKS"
+elif [ "$INSTALL_ALL" = true ]; then
   PACKS="$ALL_PACKS"
   echo "Installing all $(echo "$PACKS" | wc -l | tr -d ' ') packs..."
 else

tests/install.bats

@@ -264,3 +264,25 @@ print('OK')
   [ -f "$INSTALL_DIR/packs/peon/openpeon.json" ]
   [ ! -f "$INSTALL_DIR/packs/peon/manifest.json" ]
 }
+
+@test "--packs installs only specified packs" {
+  bash "$CLONE_DIR/install.sh" --packs=peon,glados
+  [ -d "$INSTALL_DIR/packs/peon" ]
+  [ -d "$INSTALL_DIR/packs/glados" ]
+  # Should NOT have other default packs
+  [ ! -d "$INSTALL_DIR/packs/peasant" ]
+  [ ! -d "$INSTALL_DIR/packs/duke_nukem" ]
+}
+
+@test "--packs with single pack works" {
+  bash "$CLONE_DIR/install.sh" --packs=peon
+  [ -d "$INSTALL_DIR/packs/peon" ]
+  pack_count=$(ls -d "$INSTALL_DIR/packs/"*/ 2>/dev/null | wc -l | tr -d ' ')
+  [ "$pack_count" -eq 1 ]
+}
+
+@test "--packs overrides default pack list" {
+  bash "$CLONE_DIR/install.sh" --packs=glados
+  [ -d "$INSTALL_DIR/packs/glados" ]
+  [ ! -d "$INSTALL_DIR/packs/peon" ]
+}