feat(Unity): ANR (#7537)

Author: bitsandfoxes

src/platforms/unity/configuration/app-not-responding.mdx

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+---
+title: App Not Responding (ANR)
+sidebar_order: 20
+description: "Learn how to turn off or specify ANR."
+---
+
+Application Not Responding (ANR) errors are triggered when the Unity thread of the game is blocked for more than five seconds. The Unity SDK reports ANR errors as Sentry events.
+
+## ANR Implementation Details
+
+The ANR detection in the Unity SDK strictly works within the Unity game, ireespecitve of the targeted platform and works in two parts. First the SDK starts a coroutine that periodically notes the time it last got called. Second, a background thread checks the time since the last update against the ANR threshold from the options.
+The detection is sensitive of the app losing and regaining focus and gets paused accordingly. It is also using `WaitForSecondsRealtime` so pausing your game by modifying the `Time.timeScale` will not trigger false ANR reports.
+
+On platforms that do no support multithreading the ANR detection falls back to relying on the coroutine itself to report if the last time it executed exceeds the timeout.
+
+## Configuration
+
+ANR detection is enabled by default in Sentry, but you can opt-out through the editor window by going to `Tools -> Sentry -> Advanced -> ANR Detection`. You can also set the ANR timeout there.
+
+![ANR Detection](unity-anr.jpg)
+
+You can also opt out by disabling the integration.
+
+```csharp
+options.DisableAnrIntegration();
+```
+
+To set the timeout use the following snippet.
+
+```csharp
+options.AnrTimeout = TimeSpan.FromSeconds(5);
+```