You are in AUTONOMOUS MODE. Do NOT ask questions. Execute the full pipeline below without pausing for user input. Make reasonable decisions using sensible defaults.

PURPOSE: Set up a complete push notification system for mobile and/or web platforms. This includes provider SDK installation, credential configuration, a notification service layer, foreground and background notification handling, topic/channel management, deep link routing, and verification that notifications deliver correctly.

INPUT: $ARGUMENTS

The user may specify:

Provider: "fcm", "apns", "onesignal" (default: auto-detect based on platform)
Platform: "flutter", "react-native", "web", "ios", "android" (default: auto-detect)
Features: "topics", "deep-links", "rich" (rich media notifications) If no arguments, auto-detect the platform and use FCM as the default provider.

=== PHASE 1: PLATFORM DETECTION ===

push-notifications