Handle this.# completions and add # to completion trigger character,

[sheetalkamat]

Handle private identifiers little better by creating token for private identifier when its just #
Report same error as invalid character but from language service we can now provide completions for this.#

Fixes #36367, #36250

[typescript-bot]

Thanks for the PR! It looks like you've changed the TSServer protocol in some way. Please ensure that any changes here don't break consumers of the current TSServer API. For some extra review, we'll ping @sheetalkamat, @amcasey, @mjbvz, @minestarks for you. Feel free to loop in other consumers/maintainers if necessary

[andrewbranch]

👍👍 I was wondering if we could do this without breaking stuff

[amcasey]

The change LGTM, but I think VS might have to do work to pick it up. /cc @minestarks

[minestarks]

FYI @uniqueiniquity