Record the Windows beta13 preview candidate

[coneilen]

Summary

Record the immutable, unpublished Windows beta13 preview candidate and its
LFS-aware Dev Box handoff. Beta12 is failed and superseded. Stop worked in the
daemon, but the shell decoded the daemon's LoopState object as idle, so the
Stop UI never updated. #647 fixes this. All runtime qualification gates remain
open.

Changes

• Record source/tag/package/payload/executable/provider/toolchain identities for
  0.1.78-windows.beta13 at af3d006146d8d9aad52b5621499d287d862ab3de.
• Record the Fix Windows Stop UI synchronization #647 fix and the fully passing local Windows-shell validation at
  the candidate source.
• Record custody, the offline restore (43/43 LFS) and the 8/8 handoff.
• Move beta12 to history, keeping beta1–beta12 unchanged.
• Keep Exact artifact complete, the other six gates open, and parity at
  98/60/38.

Test plan

RED: PR 647 zig test src\App.zig --test-filter "open workspace applies production stopped state" before the fix -> expected stopped, found idle; 0 passed, 1 failed
GREEN: Tools\windows\validate.ps1 -Task windows-shell -SkipTrayLive -ShellValidationRoot C:\v7 at af3d006 -> VALIDATE_EXIT=0; 55/55 sections; App 773/773; scrubbed 5/5; real daemon round trip PASS; live UIA gate PASS
REGRESSION: Tools\windows\release.ps1 -Tag 0.1.78-windows.beta13 -> repository verify 1 PASS; extracted setup verify 1 PASS; payload 50; binary reports deferred; packaged scrubbed startup 5/5

• The RED line is from Fix Windows Stop UI synchronization #647's own evidence and exact-head CI. I did not
  reproduce it locally.
• Source custody Create/Verify passed, 43 objects for 43 files. The file-only
  offline restore produced the exact detached HEAD/tag, zero remotes, clean
  status and 43/43 materialized LFS files.
• Handoff inventory: 8/8 verified; hashes.sha256 SHA-256
  5cd562a1a907f8897614d32242889fc4e6da856eb708c7c644e2f713e5f0bc57.
• Not claimed: the Dev Box Stop rerun, backend, terminal pixels, destructive,
  Worktrees, Nod, dump or publication evidence.
• No tag or release was pushed or published.
• macOS make test/make check were not run; this is a documentation-only
  update.

Checklist

• I have read the Contributing Guidelines
• I have signed off my commits (git commit -s) per the DCO
• Tests pass locally (make test)
• Code follows the existing style (make check)
• I added the test/contract before the implementation and observed the intended RED failure