chore: docs improvements (#9142)

Improvements to `select` docs and `jobs-queue` docs

docs/jobs-queue/tasks.mdx

@@ -0,0 +1,141 @@
+---
+title: Tasks
+label: Tasks
+order: 20
+desc: A Task is a distinct function declaration that can be run within Payload's Jobs Queue. 
+keywords: jobs queue, application framework, typescript, node, react, nextjs
+---
+
+<Banner type="default">
+  A <strong>"Task"</strong> is a function definition that performs business logic and whose input and output are both strongly typed.
+</Banner>
+
+You can register Tasks on the Payload config, and then create [Jobs](/docs/beta/jobs-queue/jobs) or [Workflows](/docs/beta/jobs-queue/workflows) that use them. Think of Tasks like tidy, isolated "functions that do one specific thing".
+
+Payload Tasks can be configured to automatically retried if they fail, which makes them valuable for "durable" workflows like AI applications where LLMs can return non-deterministic results, and might need to be retried.
+
+Tasks can either be defined within the `jobs.tasks` array in your payload config, or they can be defined inline within a workflow.
+
+### Defining tasks in the config
+
+Simply add a task to the `jobs.tasks` array in your Payload config. A task consists of the following fields:
+
+| Option                      | Description                                                                      |
+| --------------------------- | -------------------------------------------------------------------------------- |
+| `slug` | Define a slug-based name for this job. This slug needs to be unique among both tasks and workflows.|
+| `handler`   | The function that should be responsible for running the job. You can either pass a string-based path to the job function file, or the job function itself. If you are using large dependencies within your job, you might prefer to pass the string path because that will avoid bundling large dependencies in your Next.js app.         |
+| `inputSchema` | Define the input field schema - payload will generate a type for this schema. |
+| `interfaceName` | You can use interfaceName to change the name of the interface that is generated for this task. By default, this is "Task" + the capitalized task slug. |
+| `outputSchema` | Define the output field schema - payload will generate a type for this schema. |
+| `label` | Define a human-friendly label for this task. |
+| `onFail` | Function to be executed if the task fails. |
+| `onSuccess` | Function to be executed if the task succeeds. |
+| `retries` | Specify the number of times that this step should be retried if it fails. |
+
+The logic for the Task is defined in the `handler` - which can be defined as a function, or a path to a function. The `handler` will run once a worker picks picks up a Job that includes this task.
+
+It should return an object with an `output` key, which should contain the output of the task as you've defined.
+
+Example:
+
+```ts
+export default buildConfig({
+  // ...
+  jobs: {
+    tasks: [
+      {
+        // Configure this task to automatically retry
+        // up to two times
+        retries: 2,
+
+        // This is a unique identifier for the task
+
+        slug: 'createPost',
+
+        // These are the arguments that your Task will accept
+        inputSchema: [
+          {
+            name: 'title',
+            type: 'text',
+            required: true,
+          },
+        ],
+
+        // These are the properties that the function should output
+        outputSchema: [
+          {
+            name: 'postID',
+            type: 'text',
+            required: true,
+          },
+        ],
+
+        // This is the function that is run when the task is invoked
+        handler: async ({ input, job, req }) => {
+          const newPost = await req.payload.create({
+            collection: 'post',
+            req,
+            data: {
+              title: input.title,
+            },
+          })
+          return {
+            output: {
+              postID: newPost.id,
+            },
+          }
+        },
+      } as TaskConfig<'createPost'>,
+    ]
+  }
+})
+```
+
+In addition to defining handlers as functions directly provided to your Payload config, you can also pass an _absolute path_ to where the handler is defined. If your task has large dependencies, and you are planning on executing your jobs in a separate process that has access to the filesystem, this could be a handy way to make sure that your Payload + Next.js app remains quick to compile and has minimal dependencies.
+
+In general, this is an advanced use case. Here's how this would look:
+
+`payload.config.ts:`
+
+```ts
+import { fileURLToPath } from 'node:url'
+import path from 'path'
+
+const filename = fileURLToPath(import.meta.url)
+const dirname = path.dirname(filename)
+
+export default buildConfig({
+  jobs: {
+    tasks: [
+      {
+        // ...
+        // The #createPostHandler is a named export within the `createPost.ts` file
+        handler: path.resolve(dirname, 'src/tasks/createPost.ts') + '#createPostHandler',
+      }
+    ]
+  }
+})
+```
+
+Then, the `createPost` file itself:
+
+`src/tasks/createPost.ts:`
+
+```ts
+import type { TaskHandler } from 'payload'
+
+export const createPostHandler: TaskHandler<'createPost'> = async ({ input, job, req }) => {
+  const newPost = await req.payload.create({
+    collection: 'post',
+    req,
+    data: {
+      title: input.title,
+    },
+  })
+  return {
+    output: {
+      postID: newPost.id,
+    },
+  }
+}
+```