Use PA-specific tmux config for power mode theme

Both pa-mode and pa-launch now use ~/.tmux-pa.conf which applies
a Dracula purple theme to visually distinguish privileged sessions.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

automation/pa-launch

@@ -32,5 +32,6 @@ else
     export PA_SESSION_ID="$session_id"
     export PA_HISTORY_FILE="$HISTORY_DIR/${session_id}.jsonl"
 
-    tmux new-session -s "$SESSION" "$CLAUDE" --dangerously-skip-permissions --agent personal-assistant
+    # Uses PA-specific config for distinct "power mode" visual theme
+    tmux -f ~/.tmux-pa.conf new-session -s "$SESSION" "$CLAUDE" --dangerously-skip-permissions --agent personal-assistant
 fi