fix: Reinstall native backend (#1603)

Author: bitsandfoxes

Diff for: CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Fixes
 
+- The SDK no longer fails to capture native crashes on Windows. It now properly reinstalls the capturing backend during the initialization ([#1603](https://github.com/getsentry/sentry-unity/pull/1603))
 - When building for iOS, the SDK no longer adds its dependencies multiple times (#1558) ([#1595](https://github.com/getsentry/sentry-unity/pull/1595))
 
 ### Dependencies

Diff for: src/Sentry.Unity.Native/SentryNative.cs

@@ -69,6 +69,11 @@ public static void Configure(SentryUnityOptions options, ISentryUnityInfo sentry
                 }
             }
             options.CrashedLastRun = () => crashedLastRun;
+
+            // At this point Unity has taken the signal handler and will not invoke our handler. So we register our
+            // backend once more to make sure user-defined data is available in the crash report and the SDK is able
+            // to capture the crash.
+            SentryNativeBridge.ReinstallBackend();
         }
     }
 }

Diff for: src/Sentry.Unity.Native/SentryNativeBridge.cs

@@ -104,6 +104,8 @@ internal static string GetCacheDirectory(SentryUnityOptions options)
             }
         }
 
+        internal static void ReinstallBackend() => sentry_reinstall_backend();
+
         // libsentry.so
         [DllImport("sentry")]
         private static extern IntPtr sentry_options_new();
@@ -276,5 +278,8 @@ private static void WithMarshalledStruct<T>(T structure, Action<IntPtr> action)
 
         [DllImport("sentry")]
         private static extern int sentry_clear_crashed_last_run();
+
+        [DllImport("sentry")]
+        private static extern void sentry_reinstall_backend();
     }
 }