docs(dart): Add feature flags documentation

docs/platforms/dart/common/feature-flags/index.mdx

@@ -0,0 +1,27 @@
+---
+title: Set Up Feature Flags
+sidebar_order: 7000
+description: With Feature Flags, Sentry tracks feature flag evaluations in your application, keeps an audit log feature flag changes, and reports any suspicious updates that may have caused an error.
+---
+
+<PlatformContent includePath="feature-flags/prerelease-alert" />
+
+## Prerequisites
+
+- [Sentry SDK](/platforms/dart/#configure) version `9.0.0` or higher is installed.
+
+## Enable Evaluation Tracking
+
+If you use a third-party SDK to evaluate feature flags, you can enable a Sentry SDK integration to track those evaluations. Integrations are provider specific. Documentation for supported SDKs is listed below.
+
+- [Firebase Remote Config](/platforms/dart/configuration/integrations/firebase-remote-config/)
+
+### Manual Usage
+
+Call `Sentry.addFeatureFlag` to track feature flag evaluations.
+
+```dart
+Sentry.addFeatureFlag("feature_flag_a", true);
+```
+
+Calling this function multiple times with the same flag name will override the previous value.

docs/platforms/dart/common/integrations/firebase-remote-config.mdx

@@ -0,0 +1,9 @@
+---
+title: Firebase Remote Config
+description: "Learn more about the Sentry Firebase Remote Config integration for the Dart SDK."
+sidebar_order: 50
+redirect_from:
+  - /platforms/dart/guides/firebase-remote-config/
+---
+
+<Include name="dart-integrations/firebase-remote-config.mdx" />

docs/platforms/dart/guides/flutter/integrations/firebase-remote-config.mdx

@@ -0,0 +1,9 @@
+---
+title: Firebase Remote Config
+description: "Learn more about the Sentry Firebase Remote Config integration for the Flutter SDK."
+sidebar_order: 60
+redirect_from:
+  - /platforms/dart/guides/flutter/firebase-remote-config/
+---
+
+<Include name="dart-integrations/firebase-remote-config.mdx" />

includes/dart-integrations/firebase-remote-config.mdx

@@ -0,0 +1,59 @@
+---
+title: Firebase Remote Config
+description: "Learn more about the Sentry Firebase Remote Config integration for the Dart SDK."
+sidebar_order: 6
+platforms:
+  - flutter
+---
+
+The `sentry_firebase_remote_config` integration provides [Firebase Remote Config](https://firebase.google.com/docs/remote-config/get-started?platform=flutter) support for Sentry thus providing insight into feature flag evaluations.
+
+## Behavior
+
+- Adding the `SentryFirebaseRemoteConfig` integration will automatically track feature flag evaluations.
+- Only boolean values are supported.
+
+## Prerequisites
+
+1. [Sentry SDK](/platforms/dart/#configure) version `9.0.0` or higher is installed.
+2. Firebase Remote Config is set up.
+
+## Install
+
+To use the `SentryFirebaseRemoteConfig` integration, add the `sentry_firebase_remote_config` dependency.
+
+```yml {filename:pubspec.yaml}
+dependencies:
+  sentry: ^9.0.0
+  sentry_firebase_remote_config: ^9.0.0
+```
+
+## Configure
+
+Add the `SentryFirebaseRemoteConfig` integration to the Sentry SDK initialization. The integration will automatically call `await remoteConfig.activate();` when the config is updated.
+If you don't want this behavior, you can set `activateOnConfigUpdated` to `false`.
+
+```dart
+await SentryFlutter.init(
+  (options) {
+    options.addIntegration(
+      SentryFirebaseRemoteConfigIntegration(
+        firebaseRemoteConfig: firebaseRemoteConfig,
+        activateOnConfigUpdated: false,
+      ),
+    );
+  },
+);
+```
+
+## Verify & View
+
+### 1. Update Firebase Remote Config value
+
+Update a boolean [Firebase Remote Config](https://firebase.google.com/docs/remote-config/get-started?platform=flutter) value to true. Keep in mind that values will be evaluated as bool if there string values are `true`, `false`, `1`, or `0`. So keep in mind that numerical values of `1` or `0` will be evaluated as `true` or `false` boolean values.
+
+### 2. View the Recorded Feature Flag Evaluation on Sentry.io
+
+To view the recorded feature flag evaluation, log into [sentry.io](https://sentry.io) and open your project.
+
+The recorded feature flag evaluations will be visible in the event context.

includes/dart-integrations/index.mdx

@@ -14,7 +14,7 @@
 | [`Slow and Frozen Frames`](/platforms/dart/guides/flutter/integrations/slow-and-frozen-frames-instrumentation) | ✓ * |  |      ✓     |                        |
 | [`Sqflite`](/platforms/dart/guides/flutter/integrations/sqflite-instrumentation) |                  |            |      ✓      |                        |
 | [`User Interaction`](/platforms/dart/guides/flutter/integrations/user-interaction-instrumentation) |    |        |      ✓      |           ✓            |
-
+| [`Firebase Remote Config`](/platforms/dart/guides/flutter/integrations/firebase-remote-config) | | | | ✓ |
 <Alert>
 
 *Slow and Frozen Frames* should work automatically, however if `WidgetsFlutterBinding` is initialized before `SentryFlutter.init`, then this instrumentation will not work automatically.

src/middleware.ts

@@ -578,6 +578,10 @@ const USER_DOCS_REDIRECTS: Redirect[] = [
     from: '/platforms/dart/configuration/integrations/dio/',
     to: '/platforms/dart/integrations/dio/',
   },
+  {
+    from: '/platforms/dart/configuration/integrations/firebase-remote-config/',
+    to: '/platforms/dart/integrations/firebase-remote-config/',
+  },
   {
     from: '/quickstart/',
     to: '/platforms/',