refactor: Remove timeout_minutes parameter from action (#482)

This change removes the custom timeout_minutes parameter from the action in favor of using GitHub Actions' native timeout-minutes feature.

Changes:
- Removed timeout_minutes input from action.yml and base-action/action.yml
- Removed all timeout handling logic from base-action/src/run-claude.ts
- Updated base-action/src/index.ts to remove timeoutMinutes parameter
- Removed timeout-related tests from base-action/test/run-claude.test.ts
- Removed timeout_minutes from all example workflow files (19 files)

Rationale:
- Simplifies the codebase by removing custom timeout logic
- Users can use GitHub Actions' native timeout-minutes at the job/step level
- Reduces complexity and maintenance burden
- Follows GitHub Actions best practices

BREAKING CHANGE: The timeout_minutes parameter is no longer supported. Users should use GitHub Actions' native timeout-minutes instead.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-authored-by: Claude <noreply@anthropic.com>

examples/claude-pr-path-specific.yml

@@ -27,7 +27,6 @@ jobs:
         uses: anthropics/claude-code-action@v1-dev
         with:
           anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
-          timeout_minutes: "60"
           prompt: |
             Please review this pull request focusing on the changed files.
             Provide feedback on: