release: winTerm 1.4.2 stable

[HelloThisWorld]

Summary

Prepare winTerm 1.4.2 as the safeguarded stable patch release after the
immutable v1.4.1 tag stopped before GitHub Release creation on the exact
release-note signing-heading contract.

Related issues

Closes #

Detailed changes

• Preserve the fully validated Pane Search and Click to position cursor
  application payload from the 1.4.1 candidate.
• Advance authoritative application, package, PowerShell module, Windows
  resource, workspace fallback, shell, README, progress, and validation
  surfaces to stable 1.4.2.
• Add docs/releases/1.4.2.md with the canonical ## Signing heading,
  exactly one unsigned-installer disclosure, and SmartScreen guidance.
• Record why the published v1.4.1 tag remains immutable and why the
  correction uses a new patch version.

Validation performed

• Windows 11 x64, PowerShell 7:
  • pwsh -NoProfile -File .\scripts\winterm\verify-version.ps1 — PASS
  • pwsh -NoProfile -File .\scripts\winterm\verify-branding.ps1 — PASS
  • pwsh -NoProfile -File .\scripts\winterm\test-visual-progress.ps1 -SourceOnly — PASS
  • pwsh -NoProfile -File .\scripts\winterm\test.ps1 -Suite Smoke -Configuration Debug -Platform x64 — PASS
  • git diff --check — PASS
• The immediately preceding 1.4.1 payload passed the full local Debug x64
  build, Relevant suite, and compiled Settings Model 381/381, Terminal App
  51/51, and Control 93/93 suites. The v1.4.2 PR workflow must rebuild and
  rerun the compiled Release x64 validation under the updated metadata.
• Interactive multi-shell GUI exercises were not rerun for this metadata-only
  patch.

Checklist

• The change is focused and does not include unrelated formatting.
• Tests were added or updated where appropriate.
• All tests claimed above actually ran and passed.
• User-facing behavior and limitations are documented in this repository.
• This source/docs commit updates the root CHANGELOG.md.
• The Wiki Development-Changes.md ledger has been pushed with the final source SHA, link, summary, and checkpoint/release.
• Documentation screenshots reuse a suitable existing sanitized winterm-site asset, or no screenshot was added.
• Version or schema changes include compatibility and migration notes.
• Package identity, winterm.exe, and Microsoft Terminal coexistence remain isolated.
• No command text, terminal output, clipboard content, credentials, or private paths are logged.
• New source and script files contain the appropriate MIT license header.
• I did not include generated build output, secrets, certificates, or local absolute paths.