Workflows: NonRetryableErrors Section Improvement (#17819)

* Reenforce that for NonRetryableErrors, users need to manage the error or the Workflow will fail
* Added code example to catch NonRetryableError

---------

Co-authored-by: Sidhartha Chatterjee <[email protected]>
Co-authored-by: Matt Silverlock <[email protected]>

Author: 3 people

src/content/docs/workflows/build/sleeping-and-retrying.mdx

@@ -87,7 +87,7 @@ let someState = step.do("call an API", {
 }, async () => { /* Step code goes here /* }
 ```
 
-## Force a Workflow to fail
+## Force a Workflow instance to fail
 
 You can also force a Workflow instance to fail and _not_ retry by throwing a `NonRetryableError` from within the step.
 
@@ -111,3 +111,38 @@ export class MyWorkflow extends WorkflowEntrypoint<Env, Params> {
 ```
 
 The Workflow instance itself will fail immediately, no further steps will be invoked, and the Workflow will not be retried.
+
+## Catch Workflow errors
+
+Any uncaught exceptions that propagate to the top level, or any steps that reach their retry limit, will cause the Workflow to end execution in an `Errored` state.
+
+If you want to avoid this, you can catch exceptions emitted by a `step`. This can be useful if you need to trigger clean-up tasks or have conditional logic that triggers additional steps.
+
+To allow the Workflow to continue its execution, surround the intended steps that are allowed to fail with a `try-catch` block.
+
+
+```ts
+...
+await step.do('task', async () => {
+	// work to be done
+});
+
+try {
+    await step.do('non-retryable-task', async () => {
+		// work not to be retried
+        throw new NonRetryableError('oh no');
+    });
+} catch(e as Error) {
+    console.log(`Step failed: ${e.message}`);
+    await step.do('clean-up-task', async () => {
+      // Clean up code here
+    });
+}
+
+// the Workflow will not fail and will continue its execution
+
+await step.do('next-task', async() => {
+	// more work to be done
+});
+...
+```