Support in-place publishing page conversion with existing parameters

[TaoziZ03]

Type

• Bug Fix
• New Feature
• Sample

Related changes

Companion runtime behavior: pnp/pnpframework#1290.

What is in this Pull Request?

ConvertTo-PnPPage -PublishingPage supports conversion within the currently connected Web. The existing -TargetWebUrl and -TargetConnection parameters select an explicit target, and the cmdlet's public parameter surface is unchanged.

The companion Framework determines the transformation mode from the actual Site and Web identities. Same-Web conversion requires an existing writable Site Pages library, retains the source publishing page, and rejects an existing target even with -Overwrite.

The local Framework reference declares its required runtime dependencies and uses the selected build configuration. Help, examples, and the changelog list publishing pages among the page types supported for in-place conversion.

Validation

• Debug build against the local companion Framework passed: 0 warnings, 0 errors.
• A fresh staged module executed HTML transformation with private dependencies, verified the loaded companion DLL by SHA-256, and validated all 15 documented examples against the compiled command.
• PublishingPage remains optional; no additional in-place switch or Framework option exists.
• Companion Framework tests: 25 passed, 0 failed, 0 skipped; all four target-framework builds passed.
• Live Enterprise Wiki tests passed for same-Web conversion without target parameters and cross-site conversion through both existing target parameters.
• Three non-Enterprise-Wiki Publishing pages were each tested in-site and cross-site: rich ArticleLeft, simple ArticleLeft with List web part, and custom IPKit_Home. All six generated native modern drafts and completed editor save/exit. All original source hashes/identities/versions remained unchanged.
• The rich ArticleLeft test exposed missing-file image JSON failure. The companion Framework now returns numeric defaults and a warning for a missing image. All 31 checked body blocks, 8 tables, and 3 Image web parts persisted; the 404 image references remain unresolved.
• IPKit_Home converted using the existing -PageLayoutMapping parameter and a mapping verified against its body field and zone IDs. All 16 checked body blocks persisted. Default automatic mapping fails for this tenant's catalog item, which lacks PublishingAssociatedContentType.
• Cross-site retained existing missing-target-list skip behavior (1 List web part on each ArticleLeft fixture; 4 on IPKit_Home). Same-Web retained the lists. Default Script Editor behavior is unchanged. These tests do not claim full page/asset/list/script fidelity.
• Existing-target -Overwrite, missing Site Pages, and different-Web/same-site-collection negatives behaved as expected. Failed mapping runs produced no target page.
• Enterprise Wiki SVG remains a readable source reference under the existing copy allow-list.
• git diff --check passed.
• The ordinary package build has an independently observed CS1705: Framework 1.21.49-nightly references Core assembly 1.18.51.0 while the feed resolves Core 1.18.47-nightly. Local companion-build validation passed.

This remains a draft pending the companion Framework runtime release. Live acceptance is scoped to the tested tenant, stock Enterprise Wiki/ArticleLeft layouts, and the supplied IPKit_Home mapping.