PlatyPS 2e: convert committed docs/ markdown to the 1.x schema

[tablackburn]

Part of #120 (Phase 2 — PlatyPS migration, #105).

Scope

One-shot conversion of this repository's committed markdown under docs/ from the 0.14.x schema to the 1.x schema. Separate from the function migrations because it is a data change, not a code change, and produces a large mechanical diff that should not be mixed into a reviewable code PR.

$mdfiles = Measure-PlatyPSMarkdown -Path .\docs\en-US\*.md
$mdfiles | Where-Object Filetype -match 'CommandHelp' |
    Import-MarkdownCommandHelp -Path { $_.FilePath } |
    Export-MarkdownCommandHelp -OutputFolder .\docs\en-US -Force

Watch for

• Review the diff for content loss, not just schema churn — hand-written examples and notes are the parts most likely to be dropped in conversion
• This repo's own docs are the only consumer being migrated here. Consumers with committed docs/ face the same conversion, so whatever is learned doing it belongs in docs/migration-v0.8-to-v1.0.md as consumer guidance — that guidance is a deliverable of this issue, not an afterthought

Done when

docs/ is on the 1.x schema, no content was lost, and the migration guide documents the equivalent one-shot for consumers.