Add Moonraker Update Manager integration

🎉 One-click updates from Mainsail/Fluidd UI!

New files:
- moonraker/update_manager.cfg - Moonraker config
- moonraker/README.md - Setup instructions
- install.sh - Auto-install/update script
- README.md - Complete project documentation

Features:
✅ Update Manager entry in Mainsail/Fluidd
✅ One-click updates from web UI
✅ Automatic Klipper restart after update
✅ Safe install (doesn't overwrite custom user_settings.cfg)
✅ Installs calibration macros automatically
✅ Professional update workflow

Setup:
1. Add [include open4neptune-new/moonraker/update_manager.cfg] to moonraker.conf
2. Restart Moonraker
3. Machine → Update Manager → open4neptune-configs → Update

Like official Klipper plugins! 🔥

moonraker/update_manager.cfg

@@ -0,0 +1,19 @@
+# ============================================================================
+# MOONRAKER UPDATE MANAGER - Neptune 4 Plus Configs
+# ============================================================================
+# This file configures Moonraker to track the open4neptune-new repository
+# and allow updates directly from Mainsail/Fluidd UI
+# ============================================================================
+
+[update_manager open4neptune-configs]
+type: git_repo
+path: ~/printer_data/config/open4neptune-new
+origin: https://git.sky-net.it/nocci/open4neptune-new.git
+install_script: install.sh
+managed_services: klipper
+primary_branch: main
+allow_offline_updates: False
+update_sensors:
+    /tmp/open4neptune-last-check
+persisted_version: /tmp/open4neptune-version
+needs_refresh: True