Finalize paste api and drop api tweaks

Fixes #30066

This finalizes the documentPaste api. This api allows extensions to attach metadata on text copy and change how content is pasted. Some examples:

- Updating imports for pasted code
- Inserting an image as an attachment in notebooks
- Pasting files converts them to relative text paths

extensions/typescript-language-features/package.json

@@ -13,7 +13,6 @@
     "mappedEditsProvider",
     "codeActionAI",
     "codeActionRanges",
-    "documentPaste",
     "editorHoverVerbosityLevel"
   ],
   "capabilities": {