Lane 17: Plan deferred Windows distribution surface

[mdheller]

Track Windows distribution without distracting from the current Linux/macOS priority.

Scope:

• Define Windows package targets: WinGet, MSIX, Chocolatey, and Microsoft Store as later promotion channels.
• Preserve BearBrowser product identity: app name, app id, icon, installer metadata, and no upstream product branding.
• Define signing requirements for Windows packages.
• Keep this lane deferred until Linux and macOS primary distribution lanes are further along.

Initial packaging order:

1. WinGet / installer metadata
2. MSIX
3. Chocolatey
4. Microsoft Store

Acceptance criteria for activation:

• Linux first-class packaging lane is no longer scaffold-only.
• macOS signed/notarized app path is working.
• Windows package plan includes signing, app identity, uninstall behavior, and update path.