Add backlog plugin

[7nohe]

Plugin Submission Form

1. Metadata

• Plugin Author: 7nohe
• Plugin Name: backlog
• Repository URL: https://github.com/7nohe/dify-plugin-backlog

2. Submission Type

• New plugin submission
• Version update for existing plugin

3. Description

This PR submits a new tool-type plugin “Backlog (Nulab) Tools” that enables operating Backlog projects and issues directly from Dify.

Provided tools (7):

• List Projects: GET /api/v2/projects
• List Issues: GET /api/v2/issues (count/offset paging, returns aggregated results)
• Get Issue: GET /api/v2/issues/{issueIdOrKey}
• Create Issue: POST /api/v2/issues
• Add Comment: POST /api/v2/issues/{issueIdOrKey}/comments
• List Priorities: GET /api/v2/priorities
• List Issue Types: GET /api/v2/projects/{projectIdOrKey}/issueTypes

4. Checklist

• I have read and followed the Publish to Dify Marketplace guidelines
• I have read and comply with the Plugin Developer Agreement
• I confirm my plugin works properly on both Dify Community Edition and Cloud Version
• I confirm my plugin has been thoroughly tested for completeness and functionality
• My plugin brings new value to Dify

5. Documentation Checklist

• Step-by-step setup instructions
• Detailed usage instructions
• All required APIs and credentials are clearly listed
• Connection requirements and configuration details
• Link to the repository for the plugin source code

Reference: see README.md for full details, parameters, examples, and acceptance criteria.

6. Privacy Protection Information

Data Collection

• This plugin does not collect or store any user personal data.
• It forwards user-provided inputs to the Backlog API and returns responses at runtime.
• Credentials (SPACE_DOMAIN, API_KEY) are handled by Dify’s secure provider mechanism and are not logged or persisted by the plugin.
• Response data may include Backlog user-related fields as returned by Backlog; the plugin does not retain this data.

Privacy Policy

• I confirm that I have prepared and included a privacy policy in my plugin package based on the Plugin Privacy Protection Guidelines (see PRIVACY.md)

[LogicOber]

Great work on the plugin structure! 🎉 Please upgrade the Dify plugin daemon / SDK to the latest version. We have new requirements for the README specification (multilingual). I'll be happy to review again. 🚀

[7nohe]

@LogicOber
Thank you for the review. I have created a new PR with the requested updates in #1299, so I will close this PR and continue the discussion there.