feat(android): aggiungi permesso INTERNET e canale nativo per aprire URL

Aggiunge INTERNET permission e la query ACTION_VIEW/https richiesta da
Android 11+ per la package visibility. Espone il MethodChannel
'com.davide.biteplan/launcher' che lancia un Intent.ACTION_VIEW con
l'URL ricevuto, senza dipendere da plugin Flutter esterni.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

android/app/src/main/AndroidManifest.xml

@@ -1,5 +1,6 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
     <uses-permission android:name="android.permission.CAMERA" />
+    <uses-permission android:name="android.permission.INTERNET" />
     <application
         android:label="BitePlan"
         android:name="${applicationName}"
@@ -42,5 +43,9 @@
             <action android:name="android.intent.action.PROCESS_TEXT"/>
             <data android:mimeType="text/plain"/>
         </intent>
+        <intent>
+            <action android:name="android.intent.action.VIEW"/>
+            <data android:scheme="https"/>
+        </intent>
     </queries>
 </manifest>

android/app/src/main/kotlin/com/davide/biteplan/MainActivity.kt

@@ -1,5 +1,29 @@
 package com.davide.biteplan
 
+import android.content.Intent
+import android.net.Uri
 import io.flutter.embedding.android.FlutterActivity
+import io.flutter.embedding.engine.FlutterEngine
+import io.flutter.plugin.common.MethodChannel
 
-class MainActivity : FlutterActivity()
+class MainActivity : FlutterActivity() {
+    private val channel = "com.davide.biteplan/launcher"
+
+    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
+        super.configureFlutterEngine(flutterEngine)
+        MethodChannel(flutterEngine.dartExecutor.binaryMessenger, channel)
+            .setMethodCallHandler { call, result ->
+                if (call.method == "launch") {
+                    val url = call.argument<String>("url")
+                    if (url != null) {
+                        startActivity(Intent(Intent.ACTION_VIEW, Uri.parse(url)))
+                        result.success(null)
+                    } else {
+                        result.error("INVALID_URL", "URL is null", null)
+                    }
+                } else {
+                    result.notImplemented()
+                }
+            }
+    }
+}