Add seasonal palettes and selection prompts

- Implement dynamic/static season support in shared PS1

- Add season selection prompts to Linux and macOS installers

dotfiles/install/install-macos-user.sh

@@ -7,14 +7,57 @@ REPO_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
 SRC_PS1="$REPO_ROOT/ps1/ps1.sh"
 DST_DIR="$HOME/.config/ps1"
 DST_PS1="$DST_DIR/ps1.sh"
+SEASON_FILE="$DST_DIR/season"
 
 MARKER_START="# >>> user ps1 (managed) >>>"
 MARKER_END="# <<< user ps1 (managed) <<<"
 
+season_mode="dynamic"
+season_choice=""
+if [[ -t 0 ]]; then
+  echo "Season mode:"
+  echo "  1) Dynamic (auto by date)"
+  echo "  2) Static (pick one season)"
+  read -r -p "Choose [1]: " season_mode_choice
+  case "${season_mode_choice}" in
+    2)
+      season_mode="static"
+      echo "Pick a season:"
+      echo "  1) Winter"
+      echo "  2) Spring"
+      echo "  3) Summer"
+      echo "  4) Autumn"
+      read -r -p "Choose [1]: " season_pick
+      case "${season_pick}" in
+        2) season_choice="spring" ;;
+        3) season_choice="summer" ;;
+        4) season_choice="autumn" ;;
+        ""|1) season_choice="winter" ;;
+        *) echo "Invalid choice, using winter."; season_choice="winter" ;;
+      esac
+      ;;
+    ""|1)
+      season_mode="dynamic"
+      ;;
+    *)
+      echo "Invalid choice, using dynamic."
+      season_mode="dynamic"
+      ;;
+  esac
+fi
+
 mkdir -p "$DST_DIR"
 cp -f "$SRC_PS1" "$DST_PS1"
 chmod 0644 "$DST_PS1"
 
+{
+  printf 'PS1_SEASON_MODE=%s\n' "$season_mode"
+  if [[ "$season_mode" == "static" && -n "$season_choice" ]]; then
+    printf 'PS1_SEASON=%s\n' "$season_choice"
+  fi
+} > "$SEASON_FILE"
+chmod 0644 "$SEASON_FILE"
+
 add_source_block() {
   local file="$1"
   [[ -f "$file" ]] || touch "$file"