Add blok, remove archived draft-js

[JackUait]

Added

blok — a headless, block-based rich text editor. Content is structured JSON blocks rather than an HTML string, so stored content stays queryable and can be rendered outside the browser.

• Demo: https://blokeditor.com/demo
• Docs: https://blokeditor.com
• License: Apache-2.0

Removed (per the contributing requirement)

draft-js — archived by Facebook, so the repository is read-only and cannot receive fixes.

• Last commit: 2022-12-14 (over three years ago)
• Never reached a 1.0 release; npm is still on 0.11.7
• Two entries in this same section are built on top of it (megadraft, react-draft-wysiwyg), so I left those alone rather than expand the scope of this PR

Guideline checklist

• Alphabetic sort order kept (alloyeditor → blok → ckeditor4-react)
• Referenced once
• One line, no wrapping
• No "React" in the description
• Direct demo and docs links included