[IDEA] Freelinks - allow to disable locally

Ref. to discussion #9957 with @pmario and @s793016

Problem

The Freelinks plugin is wonderful but I often need to locally disable specific links. I currently do this by cumbersomely inserting a ‍ (an invisible character) in the string.

Some examples for why/when local disabling of freelinking is needed:

• Headings: In a heading, say "!! The works of Homer" it is typically simply not desirable that arbitrary substrings are blue/linkified.
• Irrelevance: In the sentence "The person Foobar was born in 1984", the year is linkified just because there happens to be a book tiddler titled 1984 with no relevance to the matter...
• Over-linkification: In a typical 'book review', an authors name is often mentioned frequently even within the same paragraph.

Desired solution The above referenced discussion settled on this:

If a recognised Freelink match is immediately prefixed with ~, that specific match must not be rendered as a Freelink.

This should be sufficient to cover any/all of the described problems here above, without any special rules.. Further;

The escape character should be invisible in rendered output, so ~Title displays as plain Title.

Note In the discussion, @s793016 notes that the interaction with TiddlyWiki’s native CamelCase parser needs attention;

In particular, the implementation should be tested with CamelCase linking both enabled and disabled, to ensure that ~CamelCaseTitle remains plain text and is not re-linkified by Freelinks.