fix: restore the desk layout with the TV detached first

[nextestudios]

Summary

After Back to the PC, the desk layout came back wrong: with two stacked monitors and the TV off, the second monitor ended up beside where it was (touching the first one diagonally) instead of right below it.

Cause: restore re-enabled every screen of the backup, including the ones that were off (the TV), applied the saved positions while the TV was still part of the desktop, and only detached the TV last. Windows keeps the positions around a screen that's on and re-flows the others when it leaves.

• Only the screens that were on come back (monitorsToVerify); the ones that were off are detached before any position is applied (and not at all if the originals failed to come back, so the PC is never left without a picture).
• The saved layout is then applied to a desktop that already has its final screens, checked against the backup (new pure DisplayIdentity.LayoutMismatches) and retried up to three times.
• LoadLayout flushes the registry's display settings, which can bring a just-detached screen back. After it, anything meant to stay off that is on is detached again (two rounds), and if that moved the others the positions are set with a new CcdHelper.SetPositions: one CCD call that only touches active paths, so it never re-attaches a screen.
• The log now lists the screens meant to stay off, says when one came back and when positions were off or fixed by CCD; a monitor with no current mode is logged instead of silently skipped.
• docs/TESTING.md: a restore-layout checklist (stacked monitors + TV off, repeated cycles, a TV that was on before, an original screen that doesn't come back).

Validation

• New DisplayIdentityTests: layout check passes when every screen is where it was, flags a screen that slid aside, one that is off/missing, and ignores backups without positions.
• Verified on a real PC with 2 desk monitors + a TV (build from my fork): the layout comes back identical and the TV stays off.
• App build and dotnet test are left to CI.

🤖 Generated with Claude Code

[pullfrog]

✅ No new issues found.

Reviewed changes The restore sequence and CCD position correction for returning to the desk display layout were reviewed, along with the associated tests, manual test checklist, and changelog entries.

• Restore ordering Re-enables displays that were active in the backup, detaches previously-off displays before restoring positions, and retries when layout loading re-enables them.
• Layout validation and correction Compares restored active-display positions with the backup and uses active-path CCD positioning when needed.
• Coverage and documentation Adds pure layout mismatch tests and manual checks for display-topology restore scenarios.

  ^{｜ View workflow run ｜ Using GPT Luna ｜ 𝕏}