Write documentation section for handling errors within generators (#1281)

Author: tmcw

content/src/content/docs/docs/getting-started/using-generators.mdx

@@ -84,6 +84,9 @@ Key steps to follow when using `Effect.gen`:
 - Use `yield*` to handle effects
 - Return the final result
 
+If any of the effects that you handle inside of the generator with `yield*`
+fail, then the generator will stop and exit with that failure.
+
 <Aside type="caution" title="Required TypeScript Configuration">
   The generator API is only available when using the `downlevelIteration`
   flag or with a `target` of `"es2015"` or higher in your `tsconfig.json`
@@ -249,6 +252,8 @@ How does this affect your code? If you have several operations in sequence, once
 
 In simpler terms, if something fails at any point, the program will stop right there and deliver the error to you.
 
+If you don't want to stop on an error, you can use the `Effect.either` method to encapsulate the error in the [Either](/docs/data-types/either/) data type: see the [examples of managing expected errors](/docs/error-management/expected-errors/#either).
+
 **Example** (Halting Execution at the First Error)
 
 ```ts twoslash