Improve Plugin Docs: Add English Plugin Development Book

[charantejguniganti]

Problem

The current plugin documentation mentions that the English tutorial is still a work in progress and redirects users to a Japanese Zenn book with browser translation. This creates friction for English-speaking contributors and makes onboarding harder.

Why this matters

A proper in-doc English guide would significantly improve developer experience and align with ongoing efforts (like LFX) to make PipeCD more contributor-friendly. This section is a clear gap and a strong candidate for structured documentation.

Proposed Solution

Replace the placeholder note with a dedicated “Plugin Development Book” inside the docs.

Suggested structure:

docs/content/en/docs-v1.0.x/contribution-guidelines/contributing-plugins/book/
  _index.md
  01-architecture.md
  02-first-stage-plugin.md
  03-config.md
  04-testing.md

• Provide a structured, chapter-based learning path
• Keep the Zenn book as a reference, not the primary guide

Contribution

I’d like to work on this by creating the initial structure and drafting the first few chapters. Please let me know if this approach aligns with the project direction.

Thanks!

[charantejguniganti]

Hi @khanhtc1202

Kindly review this issue when you have some time. I’d appreciate your feedback on whether this approach aligns with the project direction, and I’m happy to proceed with implementation based on your suggestions.

Thanks!