Add GitHub Action for manual issue solving

[konard]

Summary

This PR adds a GitHub Action prototype that allows manually triggering issue solving with a GitHub issue URL as input. The workflow uses free AI models (Kimi, etc.) that require no AI provider authentication, combined with GitHub Actions' built-in GITHUB_TOKEN for gh CLI authentication.

Key Features

• Manual trigger via workflow_dispatch with issue URL input
• Free AI models support:
  • kimi-k2.5-free (default) - 262K context window
  • minimax-m2.1-free - 204K context window
  • gpt-5-nano - 200K context window
  • glm-4.7-free - 204K context window
  • big-pickle - 200K context window
• Flexible authentication:
  • Uses GITHUB_TOKEN by default (no setup required)
  • Optional PAT support for cross-repository access
• Additional options:
  • Auto-PR creation
  • Auto-fork for public repos without write access
  • Verbose logging mode

Files Changed

File	Description
.github/workflows/solve-issue.yml	Main GitHub Action workflow
docs/GITHUB_ACTIONS.md	User documentation
docs/case-studies/issue-1265/README.md	Research and design analysis

How to Use

1. Go to Actions tab in GitHub
2. Select Solve Issue workflow
3. Click Run workflow
4. Enter the issue URL (e.g., https://github.com/owner/repo/issues/123)
5. Configure options (model, auto-PR, etc.)
6. Click Run workflow

Authentication Options

Method	Use Case	Cross-Repo
GITHUB_TOKEN (default)	Same repository	No
PAT (via secret)	Any repository	Yes
Auto-fork	Public repos	Yes

Research & Design

See Case Study: Issue #1265 for detailed research on:

• Free AI models and their capabilities
• GitHub Actions authentication mechanisms
• GITHUB_TOKEN permissions and limitations
• Alternative authentication approaches

Test Plan

• Verify workflow file is valid YAML
• Test manual trigger from GitHub UI
• Test with same-repository issue
• Test with cross-repository issue (requires PAT)
• Test auto-fork functionality
• Verify all free models work without auth

References

• Issue: Make a prototype of GItHub Action, that is triggered manually, and accepts link to an issue #1265
• GitHub Actions Documentation
• Free Models Documentation

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Fixes #1265

[konard]

🤖 Solution Draft Log

This log file contains the complete execution trace of the AI solution draft process.

💰 Cost estimation:

• Public pricing estimate: $8.572219
• Calculated by Anthropic: $5.777600 USD
• Difference: $-2.794619 (-32.60%)
  📎 Log file uploaded as Gist (925KB)
  🔗 View complete solution draft log

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Now working session is ended, feel free to review and add any feedback on the solution draft.