feat(android): publish the signed release build of the wrapper

Replaces the debug APK with a release build signed with the project key
(CN=Marek Wojtaszek, valid to 2081, v1+v2 schemes, not debuggable), so
every later version installs over this one instead of forcing a reinstall.

Docs catch up with what the app can now do: QR scanning works on https
instances, downloads land in the phone's Downloads folder, and the address
form is a non-destructive screen you can reach deliberately. New SHA-256,
size, permission list and the signing fingerprint to verify against.

Also silences the Kotlin warning for the deprecated shouldOverrideUrlLoading
overload kept for Android 5.x - source-only, the APK is unaffected.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

android/src/app/src/main/java/it/wojtaszek/mc/wrapper/MainActivity.kt

@@ -140,7 +140,8 @@ class MainActivity : AppCompatActivity() {
             override fun shouldOverrideUrlLoading(view: WebView?, request: WebResourceRequest?): Boolean =
                 handleUrl(request?.url)
 
-            @Suppress("DEPRECATION")
+            // Deprecated, but it is the only one Android 5.x calls
+            @Suppress("DEPRECATION", "OVERRIDE_DEPRECATION")
             override fun shouldOverrideUrlLoading(view: WebView?, url: String?): Boolean =
                 handleUrl(if (url == null) null else Uri.parse(url))
 
@@ -228,7 +229,7 @@ class MainActivity : AppCompatActivity() {
                 setMimeType(mimeType)
                 setTitle(fileName)
                 setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, fileName)
-                setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFIED)
+                setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED)
                 if (!userAgent.isNullOrEmpty()) addRequestHeader("User-Agent", userAgent)
                 CookieManager.getInstance().getCookie(url)?.let { addRequestHeader("Cookie", it) }
             }