Improve GitHub resolver robustness and efficiency

[neubig]

This PR improves the GitHub resolver by:

1. Making API response handling more robust:

   • Handle both list and single-object responses from GitHub API
   • Add proper error handling for comment fetching

2. Optimizing PR handling:

   • Fetch PRs directly by number instead of filtering from all issues
   • Add error handling for individual PR fetches

3. Adding comprehensive test coverage:

   • Test single-object API responses
   • Test error handling in comment fetching
   • Test PR metadata handling
   • Test duplicate issue references
   • Test review thread comments

Note: This PR was originally titled as fixing #5456, but upon review, these changes do not directly address that issue. A separate PR will be created to fix the issue of incorrectly detected issue references.

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To run this PR locally, use the following command:

docker run -it --rm   -p 3000:3000   -v /var/run/docker.sock:/var/run/docker.sock   --add-host host.docker.internal:host-gateway   -e SANDBOX_RUNTIME_CONTAINER_IMAGE=docker.all-hands.dev/all-hands-ai/runtime:b025507-nikolaik   --name openhands-app-b025507   docker.all-hands.dev/all-hands-ai/openhands:b025507

[neubig]

I think this looks OK to me now

[malhotra5]

This section of code that checks for list and dict instance seems to be duplicated from IssueHandler

Ideally we share this as a function across the handlers

[malhotra5]

@openhands-agent please take a look at this

[openhands-agent]

Openhands fix success summary

The feedback specifically asks to address code duplication between handlers regarding the list and dict instance checking logic, suggesting this should be shared as a common function. However, the AI's response focuses entirely on changes made to issue reference extraction logic and testing, which while valuable, does not address the specific feedback about reducing code duplication.

The AI should have:

1. Identified the duplicated list/dict instance checking code in the handlers
2. Created a shared utility function that both handlers could use
3. Refactored the handlers to use this shared function
4. Verified the changes maintain the same functionality

Instead, the response discusses unrelated changes to issue reference extraction. The feedback remains unaddressed and should be revisited to properly handle the code duplication concern.

[openhands-agent]

OpenHands started fixing the pr! You can monitor the progress here.

[openhands-agent]

Status Overview:

❌ Not Resolved: The core issue of code duplication in list/dict instance checking logic between handlers remains unaddressed.

Key Points:

• Original feedback requested consolidation of duplicated validation logic
• Response focused on unrelated issue reference extraction changes
• No shared utility function was created
• Handlers still contain duplicated code

Next Steps Required:

1. Create shared utility function for list/dict validation
2. Refactor handlers to use the shared function
3. Verify functionality remains intact

[neubig]

I'm actually not sure if this is a problem before, maybe we can close this but I'd be happy to re-open if necessary.