feat(desktop): add --reset flag to clear user data for testing

- Add reset-user-data.sh script to clear ~/.super-multica/
- Add --reset CLI flag to clear localStorage on startup
- Add dev:reset npm script for development testing

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

scripts/reset-user-data.sh

@@ -0,0 +1,44 @@
+#!/bin/bash
+# Reset all user data for super-multica desktop app
+# Use this to simulate a fresh install for testing
+
+set -e
+
+echo "🧹 Resetting Super Multica user data..."
+
+# Main data directory
+MULTICA_DATA_DIR="$HOME/.super-multica"
+if [ -d "$MULTICA_DATA_DIR" ]; then
+  echo "  Removing $MULTICA_DATA_DIR"
+  rm -rf "$MULTICA_DATA_DIR"
+else
+  echo "  $MULTICA_DATA_DIR does not exist, skipping"
+fi
+
+# Electron app data (macOS)
+if [[ "$OSTYPE" == "darwin"* ]]; then
+  ELECTRON_APP_DATA="$HOME/Library/Application Support/super-multica"
+  if [ -d "$ELECTRON_APP_DATA" ]; then
+    echo "  Removing $ELECTRON_APP_DATA"
+    rm -rf "$ELECTRON_APP_DATA"
+  else
+    echo "  $ELECTRON_APP_DATA does not exist, skipping"
+  fi
+fi
+
+# Electron app data (Linux)
+if [[ "$OSTYPE" == "linux-gnu"* ]]; then
+  ELECTRON_APP_DATA="$HOME/.config/super-multica"
+  if [ -d "$ELECTRON_APP_DATA" ]; then
+    echo "  Removing $ELECTRON_APP_DATA"
+    rm -rf "$ELECTRON_APP_DATA"
+  else
+    echo "  $ELECTRON_APP_DATA does not exist, skipping"
+  fi
+fi
+
+echo "✅ User data reset complete!"
+echo ""
+echo "Next steps:"
+echo "  pnpm dev              # Start app (will show onboarding)"
+echo "  pnpm dev:reset        # Reset and start in one command"