Add Hogwarts Zsh theme

Introduces a new colorful two-line Zsh prompt inspired by Hogwarts houses. The theme displays user@host, time, path, git branch/status, and tmux/screen session info with distinct house colors.

themes/hogwarts.zsh-theme

@@ -0,0 +1,77 @@
+# =======================================
+# Hogwarts Zsh Theme
+# Author: TheWinterShadow
+# A colorful two-line prompt inspired by Hogwarts houses.
+# Shows user@host, time, path, git branch/status, and tmux/screen info.
+# =======================================
+
+# Enable prompt substitution (needed for $(...) and colors)
+setopt PROMPT_SUBST
+
+# Hogwarts House Colors (ANSI)
+user_color="%F{196}"       # Scarlet (Gryffindor)
+host_color="%F{34}"         # Emerald (Slytherin)
+screen_color="%F{226}"      # Gold (Hufflepuff)
+time_color="%F{226}"        # Gold (Hufflepuff)
+path_color="%F{27}"         # Ravenclaw Blue
+git_branch_color="%F{196}"  # Scarlet
+git_status_color="%F{250}"  # Light Gray
+reset_color="%f"
+
+# Git branch name
+parse_git_branch() {
+  local branch
+  branch=$(git symbolic-ref --short HEAD 2>/dev/null)
+  if [[ -n $branch ]]; then
+    echo "${git_branch_color}git:${branch}${reset_color}"
+  fi
+}
+
+# Git ahead/behind
+parse_git_arrows() {
+  git rev-parse --is-inside-work-tree &>/dev/null || return
+  local ahead behind
+  ahead=$(git rev-list --count @{u}..HEAD 2>/dev/null)
+  behind=$(git rev-list --count HEAD..@{u} 2>/dev/null)
+
+  if [[ $ahead -gt 0 || $behind -gt 0 ]]; then
+    local arrows=""
+    [[ $ahead -gt 0 ]] && arrows+="↑${ahead} "
+    [[ $behind -gt 0 ]] && arrows+="↓${behind}"
+    echo "${git_status_color}${arrows}${reset_color}"
+  fi
+}
+
+# Git clean/dirty
+parse_git_dirty() {
+  local git_changes
+  git_changes=$(git status --porcelain 2>/dev/null)
+  if [[ -n $git_changes ]]; then
+    echo "%F{196}✗%f"   # Red ✗ for dirty
+  else
+    echo "%F{34}✓%f"    # Green ✓ for clean
+  fi
+}
+
+# Screen/Tmux session indicator
+current_session() {
+  if [[ -n "$STY" ]]; then
+    echo "${screen_color}[screen:${STY}]${reset_color}"
+  elif [[ -n "$TMUX" ]]; then
+    echo "${screen_color}[tmux:$(tmux display-message -p '#S')]${reset_color}"
+  fi
+}
+
+# First line prompt
+PROMPT="%{$user_color%}%n%{$reset_color%}@%{$host_color%}%m%{$reset_color%} \
+\$(current_session) \
+%{$time_color%}[%*]%{$reset_color%} \
+%{$path_color%}%~%{$reset_color%} \
+\$(parse_git_branch) \$(parse_git_arrows) \$(parse_git_dirty)
+"
+
+# Second line input prompt
+PROMPT+="%(?.%F{34}.%F{196})❯%f "
+
+# No right prompt
+RPROMPT=''