WorkspaceSearchProvider always does regex search

[nk-coding]

Hi,
I use the search service override with the WorkspaceSearchProvider. However, if I set isRegExp: false, it still performs regex search. This can also be seen in the hosted demo of this project, e.g., by searching for ... with regex disabled (basically matches a lot is should not).

I belive the reason for this is how the search regex is created in createSerachRegex does not do any regex escaping.

I belive that this can be fixed by doing escaping similar to how vscode does it in createRegExp which is called by createSearchRegExp of their localFileSearch.ts.
Maybe it would be an option to just call the createRegExp function like vscode does? If not, I think the escaping using escapeRegExpCharacters should also do the job. However I did not test any of these options yet.

[CGNonofr]

Hi,

Do you mind opening a PR?

[nk-coding]

I can do during the next few days