* docs(claude): install manual skills at top level
* test(docs): guard Claude manual skill install path
* test(docs): detect PowerShell/$HOME nested skill-install paths
Address CodeRabbit on #2160: the nested-path regression guard only matched
Unix `mkdir`/`cp` with `~`, so a reintroduced PowerShell `Copy-Item ...
$HOME/.claude/skills/ecc` (or backslash-separated) form would have slipped
through. Extend the pattern to also cover `Copy-Item`/`New-Item` (and the
`md`/`copy`/`cpi` aliases), accept `$HOME` as an alternative to `~`, allow both
`/` and `\` separators, and match case-insensitively.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Adds de-DE docs, installer wiring, and locale tests. Pre-validated on current main with install manifest checks, markdownlint, locale-install tests, and ECC 2.0 release-surface tests.
