fix(blocks): set User-Agent header and URL-encode topic in GetWikipediaSummaryBlock (#11754)

The GetWikipediaSummaryBlock was returning HTTP 403 errors from
Wikipedia's API because it wasn't explicitly setting a User-Agent header
that complies with https://wikitech.wikimedia.org/wiki/Robot_policy.
Additionally, topics with spaces or special characters would cause
malformed URLs.

Fixes: OPEN-2889

Changes 🏗️

- URL-encode the topic parameter using urllib.parse.quote() to handle
spaces and special characters
- Explicitly set required headers per Wikimedia robot policy:
- User-Agent: Platform default user agent (includes app name, URL, and
contact email)
- Accept-Encoding: gzip, deflate: Recommended by Wikimedia to reduce
bandwidth
- Updated test mock to match the new function signature

Checklist 📋

For code changes:

- [x] I have clearly listed my changes in the PR description
- [x] I have made a test plan
- [x] I have tested my changes according to the test plan:
  - [x] Verify code passes syntax check
  - [x] Verify code passes ruff linting
- [x] Create an agent using GetWikipediaSummaryBlock with a topic
containing spaces (e.g., "Artificial Intelligence")
  - [x] Verify the block returns a Wikipedia summary without 403 errors

For configuration changes:

- .env.default 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)
.
N/A - No configuration changes required.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Bug Fixes**
* Improved Wikipedia API requests by adding compatible request headers
(including a proper user agent and encoding acceptance) for more
reliable responses.
* Enhanced handling of search topics by URL-encoding terms so queries
with spaces or special characters return correct results.

<sub>✏️ Tip: You can customize this high-level summary in your review
settings.</sub>
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

autogpt_platform/backend/backend/blocks/search.py

@@ -18,6 +18,7 @@ from backend.data.model import (
     SchemaField,
 )
 from backend.integrations.providers import ProviderName
+from backend.util.request import DEFAULT_USER_AGENT
 
 
 class GetWikipediaSummaryBlock(Block, GetRequest):
@@ -39,17 +40,27 @@ class GetWikipediaSummaryBlock(Block, GetRequest):
             output_schema=GetWikipediaSummaryBlock.Output,
             test_input={"topic": "Artificial Intelligence"},
             test_output=("summary", "summary content"),
-            test_mock={"get_request": lambda url, json: {"extract": "summary content"}},
+            test_mock={
+                "get_request": lambda url, headers, json: {"extract": "summary content"}
+            },
         )
 
     async def run(self, input_data: Input, **kwargs) -> BlockOutput:
         topic = input_data.topic
-        url = f"https://en.wikipedia.org/api/rest_v1/page/summary/{topic}"
+        # URL-encode the topic to handle spaces and special characters
+        encoded_topic = quote(topic, safe="")
+        url = f"https://en.wikipedia.org/api/rest_v1/page/summary/{encoded_topic}"
+
+        # Set headers per Wikimedia robot policy (https://w.wiki/4wJS)
+        # - User-Agent: Required, must identify the bot
+        # - Accept-Encoding: gzip recommended to reduce bandwidth
+        headers = {
+            "User-Agent": DEFAULT_USER_AGENT,
+            "Accept-Encoding": "gzip, deflate",
+        }
 
-        # Note: User-Agent is now automatically set by the request library
-        # to comply with Wikimedia's robot policy (https://w.wiki/4wJS)
         try:
-            response = await self.get_request(url, json=True)
+            response = await self.get_request(url, headers=headers, json=True)
             if "extract" not in response:
                 raise ValueError(f"Unable to parse Wikipedia response: {response}")
             yield "summary", response["extract"]