Keep PSWriteOffice website docs current from its default branch - #2374

Summary

• refresh PSWriteOffice documentation from the repository default branch during an ordinary OfficeIMO website build
• remove the stale commit lock and clean the source checkout before synchronization
• keep an explicitly selected PSWriteOfficeRoot authoritative for local branch and PR previews
• fail immediately when an explicit source is missing or is not a PSWriteOffice repository
• derive documentation counts from the ingested catalog instead of a hard-coded total
• protect the default-source and manifest behavior with website contract checks

Default and preview behavior

• Normal build: clone EvotecIT/PSWriteOffice cleanly from its remote default branch and record the resolved source manifest.
• Preview build: pass -PSWriteOfficeRoot <path> or set PSWRITEOFFICE_ROOT; that checkout supplies the documentation, recipes, command metadata, and generated pages.

This lets the public site advance automatically after PSWriteOffice changes reach its default branch while still allowing an open branch or local checkout to be previewed as one consistent revision.

Shared build invariant

Companion PowerForge PR EvotecIT/PSPublishModule#783 prevents sources-sync from being skipped by the general pipeline cache. Without that owner-level fix, repeated local builds could reuse an older source checkout even though the OfficeIMO source is configured to follow the default branch.

Validation

• post-merge default ingestion resolved the current PSWriteOffice remote HEAD (main) and passed the documentation pipeline with 123 conceptual pages
• explicit PR-checkout ingestion passed the same contracts with 123 conceptual pages
• two consecutive cache-enabled source runs executed synchronization and resolved the current remote commit
• an invalid explicit source failed before documentation synchronization