docs(contributing): Document new syntax for onboarding snippets

docs/contributing/pages/components.mdx

@@ -378,21 +378,20 @@ Attributes:
 
 ## Onboarding Options
 
-If you're writing product feature specific docs, you can specify code block `onboardingOptions` metadata:
+If you're writing product feature specific docs, you can specify markers within code blocks that enable or disable certain parts of snippets:
 
 ````markdown
-```go {"onboardingOptions": {"performance": "13-17"}}
-// your code here
+```go
+  // ___product_option_start___ performance
+  // your code here
+  // ___product_option_end___ performance
 ```
 ````
 
-the general syntax is `{"onboardingOptions": {"feature": "range"}}` where `feature` is the feature id
-and `range` is the corresponding line range (similar to the line highlighting syntax).
+the general syntax is `// ___product_option_start___ feature` where `feature` is the feature id (e.g. `performance`, `profiling` or `session-replay`).
 
 You can specify multiple features by separating them with a comma:
 
-`{"onboardingOptions": {"performance": "13-17", "profiling": "5-6"}}`
-
 The range visibility will be controlled by the `OnboardingOptionButtons` component:
 
 ```jsx diff
@@ -427,7 +426,7 @@ Example (output of the above):
   dontStick
 />
 
-```go {"onboardingOptions": {"performance": "13-17"}}
+```go
 import (
 	"fmt"
 	"net/http"
@@ -440,11 +439,13 @@ import (
 // To initialize Sentry's handler, you need to initialize Sentry itself beforehand
 if err := sentry.Init(sentry.ClientOptions{
 	Dsn: "___PUBLIC_DSN___",
+  // ___product_option_start___ performance
 	EnableTracing: true,
 	// Set TracesSampleRate to 1.0 to capture 100%
 	// of transactions for performance monitoring.
 	// We recommend adjusting this value in production,
 	TracesSampleRate: 1.0,
+  // ___product_option_end___ performance
   // Adds request headers and IP for users,
   // visit: https://docs.sentry.io/platforms/go/data-management/data-collected/ for more info
   SendDefaultPII: true,