core, ui: markdown for hyperlinks, warn on unsanitized links, option to sanitize sent links (#6160)

* core: markdown for "hidden" links

* update, test

* api docs

* chatParseUri FFI function

* ios: hyperlinks, offer to open sanitized links, an option to send sanitized links (enabled by default)

* update markdown

* android, desktop: ditto

* ios: export localizations

* core: rename constructor, change Maybe semantics for web links

* rename

bots/api/TYPES.md

@@ -1979,8 +1979,14 @@ Colored:
 Uri:
 - type: "uri"
 
+HyperLink:
+- type: "hyperLink"
+- showText: string?
+- linkUri: string
+
 SimplexLink:
 - type: "simplexLink"
+- showText: string?
 - linkType: [SimplexLinkType](#simplexlinktype)
 - simplexUri: string
 - smpHosts: [string]