Initial commit: MeshCore Open Flutter client

Open-source Flutter client for MeshCore LoRa mesh networking devices.

Features:
- BLE device scanning and connection
- Nordic UART Service (NUS) integration
- Material 3 design with system theme support
- Provider-based state management
- Placeholder screens for chat, contacts, and settings

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

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

macos/RunnerTests/RunnerTests.swift

@@ -0,0 +1,12 @@
+import Cocoa
+import FlutterMacOS
+import XCTest
+
+class RunnerTests: XCTestCase {
+
+  func testExample() {
+    // If you add code to the Runner application, consider adding tests here.
+    // See https://developer.apple.com/documentation/xctest for more information about using XCTest.
+  }
+
+}