Add ability to specify `--scope` to `winget upgrade`

Description of the new feature / enhancement

Add a switch for scope/context with winget upgrade, both for listing upgrades (specifying no apps), and when upgrading a specific app.

Example use case

List upgradeable apps

• A user without admin permissions wants to check what apps can be upgraded, thus listing system context apps makes no sense.
  • winget upgrade --scope user
• Running winget in system context, thus upgrading user context apps makes no sense.
  • winget upgrade --scope machine

Upgrade app

• Teams is installed with the system wide MSI installer, but user without admin permissions wants to upgrade Teams in user context.

  • winget upgrade --exact --id Microsoft.Teams --scope user

• A user without admin permissions wants to upgrade all user context apps.

  • winget upgrade --all --scope user

Proposed technical implementation details

Detection rules should say something about scope/context. So should the manifest too.

Edit 221221

• Changed from --context to --scope for consistency with winget install.

Start by tracing the existing winget upgrade command and compare it with the established winget install --scope behavior referenced in the issue. Done means winget upgrade --scope user and --scope machine filter listings and apply to specific and all-app upgrades, with detection rules and manifests reflecting scope or context.