[New Feature]: Enforce trailing periods (i.e., . ) for ShortDescription.

### Description of the new feature/enhancement

It simply looks more professional/cool (depending on the viewpoint) that way.

Even when disregarding zh/jp/ko locale YAML files, this would nevertheless affect more than a third of the repo's packages to varying extents: My counting with Sublime text showed around 4,150 packages of a total of just over 10,000.

### Proposed technical implementation details (optional)

Get a bot to run the following case-sensitive RegEx on the repo's packages:

`^(ShortDescription: [^一-拿㐀-䶿가-힣ぁ-ゟ゠-ヿ]{3,253}[A-Za-z0-9])(\n(# ?)?(Description|Tags|ManifestType|Moniker):.*)$` → `\1.\2`

Start by reviewing the repository's package manifests and testing the proposed case-sensitive regex against ShortDescription fields, including the locale exclusions described in the issue. Confirm how a bot could apply the change across the reported packages and define completion as the affected ShortDescription values consistently ending in periods.

Written by the indexing model from the issue text.