- Restructure project from locales/ to plugins/ directory
- Add plugin.json for each language with explicit commands/agents paths
- Consolidate root commands/, agents/ into plugins/ja/
- Update scripts/check-locales.sh to use plugins/ja as base
- Remove scripts/install.sh (replaced by /plugin install command)
- Add CLAUDE.md, COMMAND_TEMPLATE.md, README.md to each plugin

This migration enables plugin-based installation via:
/plugin install wasabeef/claude-code-cookbook/plugins/{lang}

- Register all 8 language plugins (ja, en, es, fr, ko, pt, zh-cn, zh-tw)
- Enable installation via: /plugin marketplace add wasabeef/claude-code-cookbook
- Each plugin includes commands, agents, and localized documentation

- en: Fix word order (collection of commands and roles)
- ko: Remove unnecessary spaces (를, 한국어)
- pt: Use 'papéis' (roles) instead of 'funções' (functions)

- Change from "author": "wasabeef" to "author": {"name": "wasabeef"}
- Fixes schema validation error for all 8 plugins

…ntation

Changes:
- Rename plugins: ja→cook (default), en→cook-en, ko→cook-ko, etc.
- Add "Usage" sections to all 8 language READMEs explaining prefix-based invocation
- Fix Spanish grammar: "se llaman" → "se invocan" for command invocation context
- Update marketplace.json with new plugin names
- All plugin.json files updated to match marketplace naming

Rationale:
- Japanese as default with shortest name (cook) for prioritized user experience
- Other languages use cook-XX pattern for clarity
- Prefix documentation helps users understand command invocation syntax
- Prevents namespace collisions when multiple plugins installed

Update version from 1.0.0 to 3.0.0 for marketplace metadata and all 8 language plugins to align with current release version.

- Update README.md to use new plugin names (cook, cook-en, etc.)
- Reorder language table with Japanese first as default
- Update Chinese READMEs with corrected plugin installation commands
- Fix task.md references to match new naming scheme

Add docs/ to .gitignore and remove WIP documentation files:
- plugin-directory-structure.md
- plugin-installation-guide.md
- plugin-migration-plan-simple.md
- plugin-tasks.md

These files remain locally but are no longer tracked in git.

refactor: replace to plugin architecture