Add LED tool: device, CLI, web UI, build scripts, and tests

- device.py: device communication/handling
- cli.py: CLI interface updates
- web.py: web interface
- build.py, build.sh, install.sh: build and install scripts
- Pipfile: Python dependencies
- lib/mpremote: mpremote library
- test_*.py: import and LED tests
- Updated .gitignore and README

Co-authored-by: Cursor <cursoragent@cursor.com>

test_led_simple.py

@@ -0,0 +1,35 @@
+#!/usr/bin/env python3
+"""Simple test for LED count update"""
+import json
+import sys
+import os
+
+# Add current directory to path
+sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
+
+# Test the edit logic
+edits = {}
+args_leds = 100
+
+if args_leds is not None:
+    edits["num_leds"] = args_leds
+
+print("Edits:", edits)
+
+# Simulate --no-download
+settings = {}
+
+# Apply edits
+if edits:
+    print(f"Applying {len(edits)} edit(s)...")
+    settings.update(edits)
+
+# Print settings (this is what print_settings does)
+print("\nOutput JSON:")
+print(json.dumps(settings, indent=2))
+
+# Verify
+if settings.get("num_leds") == 100:
+    print("\n✓ SUCCESS: num_leds is correctly set to 100")
+else:
+    print(f"\n✗ FAILED: num_leds is {settings.get('num_leds')}, expected 100")