feat(frontend): Add field extraction handle for block with object output (#8900)

This addresses
https://github.com/Significant-Gravitas/AutoGPT/issues/8741

We have quite a few blocks with (object) outputs. The only way to really
use these is to use a "Find In Dictionary" block to pick out that
property.

If the structure of the output object is known, we should expose the
properties of the object directly as sub-outputs. This will make a huge
difference in UX and make using these blocks much much easier.

### Changes 🏗️

Recursively flatten object fields into output node handles

<img width="637" alt="image"
src="https://github.com/user-attachments/assets/dac1f691-9866-4bb7-96b7-20fa6ddbb616">
<img width="773" alt="image"
src="https://github.com/user-attachments/assets/f8e7f97c-b245-40bd-b84f-2c044f5f9e23">


### Checklist 📋

#### For code changes:
- [ ] I have clearly listed my changes in the PR description
- [ ] I have made a test plan
- [ ] I have tested my changes according to the test plan:
  <!-- Put your test plan here: -->
  - [ ] ...

<details>
  <summary>Example test plan</summary>
  
  - [ ] Create from scratch and execute an agent with at least 3 blocks
- [ ] Import an agent from file upload, and confirm it executes
correctly
  - [ ] Upload agent to marketplace
- [ ] Import an agent from marketplace and confirm it executes correctly
  - [ ] Edit an agent from monitor, and confirm it executes correctly
</details>

#### For configuration changes:
- [ ] `.env.example` is updated or already compatible with my changes
- [ ] `docker-compose.yml` is updated or already compatible with my
changes
- [ ] I have included a list of my configuration changes in the PR
description (under **Changes**)

<details>
  <summary>Examples of configuration changes</summary>

  - Changing ports
  - Adding new services that need to communicate with each other
  - Secrets or environment variable changes
  - New or infrastructure changes such as databases
</details>

Co-authored-by: Nicholas Tindle <nicholas.tindle@agpt.co>

autogpt_platform/frontend/src/components/CustomNode.tsx

@@ -13,6 +13,7 @@ import InputModalComponent from "./InputModalComponent";
 import OutputModalComponent from "./OutputModalComponent";
 import {
   BlockIORootSchema,
+  BlockIOSubSchema,
   BlockIOStringSubSchema,
   Category,
   NodeExecutionResult,
@@ -167,17 +168,38 @@ export function CustomNode({
       nodeType === BlockUIType.NOTE
     )
       return null;
-    const keys = Object.keys(schema.properties);
-    return keys.map((key) => (
-      <div key={key}>
-        <NodeHandle
-          keyName={key}
-          isConnected={isOutputHandleConnected(key)}
-          schema={schema.properties[key]}
-          side="right"
-        />
-      </div>
-    ));
+
+    const renderHandles = (
+      propSchema: { [key: string]: BlockIOSubSchema },
+      keyPrefix = "",
+      titlePrefix = "",
+    ) => {
+      return Object.keys(propSchema).map((propKey) => {
+        const fieldSchema = propSchema[propKey];
+        const fieldTitle =
+          titlePrefix + (fieldSchema.title || beautifyString(propKey));
+
+        return (
+          <div key={propKey}>
+            <NodeHandle
+              title={fieldTitle}
+              keyName={`${keyPrefix}${propKey}`}
+              isConnected={isOutputHandleConnected(propKey)}
+              schema={fieldSchema}
+              side="right"
+            />
+            {"properties" in fieldSchema &&
+              renderHandles(
+                fieldSchema.properties,
+                `${keyPrefix}${propKey}_#_`,
+                `${fieldTitle}.`,
+              )}
+          </div>
+        );
+      });
+    };
+
+    return renderHandles(schema.properties);
   };
 
   const generateInputHandles = (

autogpt_platform/frontend/src/components/NodeHandle.tsx

@@ -10,6 +10,7 @@ type HandleProps = {
   isConnected: boolean;
   isRequired?: boolean;
   side: "left" | "right";
+  title?: string;
 };
 
 const NodeHandle: FC<HandleProps> = ({
@@ -18,6 +19,7 @@ const NodeHandle: FC<HandleProps> = ({
   isConnected,
   isRequired,
   side,
+  title,
 }) => {
   const typeName: Record<string, string> = {
     string: "text",
@@ -34,7 +36,7 @@ const NodeHandle: FC<HandleProps> = ({
   const label = (
     <div className="flex flex-grow flex-row">
       <span className="text-m green flex items-end pr-2 text-gray-900">
-        {schema.title || beautifyString(keyName.toLowerCase())}
+        {title || schema.title || beautifyString(keyName.toLowerCase())}
         {isRequired ? "*" : ""}
       </span>
       <span className={`${typeClass} flex items-end`}>