docs(#2420): clean stale get-shit-done/ path refs in translated docs (#2421)

After the package/repo rename in #604, the English docs were updated to
use gsd-core/... paths, but the four translated doc trees (ja-JP, zh-CN,
ko-KR, pt-BR) and .changeset/README.md were never updated and still
referenced the pre-rename get-shit-done/ runtime directory, which no
longer exists.

This commit brings the translations in line with the English docs:

  - docs/{ja-JP,zh-CN,ko-KR,pt-BR}/**/*.md (57 files):
      get-shit-done/ -> gsd-core/  (path references)
      #references-get-shit-donereferencesmd -> #references-gsd-corereferencesmd
                                            (anchor in INVENTORY -> ARCHITECTURE links)
  - .changeset/README.md:9 issue URL:
      open-gsd/get-shit-done-redux -> open-gsd/gsd-core

Legacy references intentionally preserved (historical record):
  - CHANGELOG.md, .changeset/archived/*, docs/RELEASE-NOTES-LEGACY.md
  - docs/cleanup-get-shit-done-cc.md, docs/adr/*, docs/research/*
  - docs/{ja-JP,ko-KR}/superpowers/plans/2026-03-18-* (developer's local paths)
  - docs/{INVENTORY,README,FEATURES,installer-migrations}.md (rename-history
    descriptions, some tagged <!-- gsd-allow-legacy-name -->)
  - Code/tests implementing or testing legacy-cleanup logic
    (bin/install.js, gsd-core/bin/lib/legacy-cleanup.cjs,
    scripts/lint-legacy-dir-name.cjs, migration sources/tests)

No source code changes — documentation only.

Fixes #2420

docs/zh-CN/references/verification-patterns.md

@@ -600,7 +600,7 @@ check_substantive() {
 
 关于自动化优先的检查点模式、服务器生命周期管理、CLI 安装处理和错误恢复协议，请参阅：
 
-**@~/.claude/get-shit-done/references/checkpoints.md** → `<automation_reference>` 部分
+**@~/.claude/gsd-core/references/checkpoints.md** → `<automation_reference>` 部分
 
 关键原则：
 - Claude 在呈现检查点**之前**设置验证环境