docs(bun): Improve bun documentation (#10576)

Author: chargome

docs/platforms/javascript/common/index.mdx

@@ -89,6 +89,15 @@ Sentry supports multiple versions of React Router. See the <PlatformLink to="/co
 
 <PlatformContent includePath="getting-started-sourcemaps" />
 
+<PlatformSection supported={["javascript.bun"]}>
+  
+  ## Use
+  
+  <PlatformContent includePath="getting-started-use" />
+  
+</PlatformSection>
+
+
 ## Verify
 
 This snippet includes an intentional error, so you can test that everything is working as soon as you set it up.

platform-includes/capture-error/javascript.bun.mdx

@@ -0,0 +1,11 @@
+You can pass an `Error` object to `captureException()` to have it captured as an event. It's also possible to pass non-`Error` objects and strings, but be aware that the resulting events in Sentry may be missing a stack trace.
+
+```javascript
+import * as Sentry from "@sentry/bun";
+
+try {
+  aFunctionThatMightFail();
+} catch (e) {
+  Sentry.captureException(e);
+}
+```

platform-includes/getting-started-config/javascript.bun.mdx

@@ -1,16 +1,25 @@
 <SignInNote />
 
-```javascript {"onboardingOptions": {"performance": "5-9"}}
+Sentry should be initialized as early in your app as possible. It is essential that you call `Sentry.init` before you require any other modules in your application—otherwise, auto-instrumentation of these modules will _not_ work.
+
+Once this is done, Sentry's Bun SDK captures unhandled exceptions as well as tracing data for your application.
+
+You need to create a file named `instrument.js` that imports and initializes Sentry:
+
+```javascript {filename: instrument.js} {"onboardingOptions": {"performance": "7-11"}}
 import * as Sentry from "@sentry/bun";
 
+// Ensure to call this before importing any other modules!
 Sentry.init({
   dsn: "___PUBLIC_DSN___",
-
+  
   // Add Performance Monitoring by setting tracesSampleRate
   // Set tracesSampleRate to 1.0 to capture 100% of transactions
   // We recommend adjusting this value in production
   tracesSampleRate: 1.0,
 });
 ```
 
-Once configured, you can capture exceptions manually, as the following example shows.
+Once you set a `tracesSampleRate`, performance instrumentation is automatically enabled for you. See <PlatformLink to="/tracing/instrumentation/automatic-instrumentation">Automatic Instrumentation</PlatformLink> to learn about all the things that the SDK automatically instruments for you.
+
+You can also manually capture performance data - see <PlatformLink to="/tracing/instrumentation/custom-instrumentation">Custom Instrumentation</PlatformLink> for details.

platform-includes/getting-started-use/javascript.bun.mdx

@@ -0,0 +1,11 @@
+You need to import the `instrument.js` file before importing any other modules in your application. This is necessary to ensure that Sentry can automatically instrument all modules in your application:
+
+```javascript {filename: app.js}
+// Import this first!
+import "./instrument";
+
+// Now import other modules
+import http from "http";
+
+// Your application code goes here
+```