**Requirements**
[x] Support a new parameter property for TemplateData, called `suggestedvalues` in JSON.
[] Implement the UI behind feature flag
[x] Add field to edit this new property in the TemplateData editor on the parameter properties page underneath the type property.
[x] Give this field a label of: "Suggested values"
[] Only have this property visible when the following parameter types are selected: Content, Line, String, Unknown, Number, Unbalanced wikitext. Otherwise, hide suggested values and its field.
[x] For input, use OOUI TagMultiselectWidget (allowArbitrary, inline input, placeholder). The items can then also include commas.
[x] Placeholder text: "Add value..."
[x] When rendering the embedded TemplateData table in an article, display the suggested values under a bold heading beneath the description, as is done for `default` and `example`.
**Mock**
{F34111807}
Relevant prototype commits:
* https://gitlab.com/wmde/mediawiki-extensions-TemplateData/-/commit/682a2552b3df4a315f2e7ab81fe34a093f3525cd
* https://gitlab.com/wmde/mediawiki-extensions-VisualEditor/-/commit/cc6ba335263f141b740202634aec483572b66cd1