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>

base-action/examples/issue-triage.yml

@@ -104,5 +104,4 @@ jobs:
           prompt_file: /tmp/claude-prompts/triage-prompt.txt
           allowed_tools: "Bash(gh label list),mcp__github__get_issue,mcp__github__get_issue_comments,mcp__github__update_issue,mcp__github__search_issues,mcp__github__list_issues"
           mcp_config: /tmp/mcp-config/mcp-servers.json
-          timeout_minutes: "5"
           anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}