(core) Copy column type and options when pasting into an empty column

Summary:
Adds a `data-grist-col-ref` attribute to the copied HTML, then uses that when pasting to look up the source column and retrieve info about it. Copies the info into the target column if:

- The document is the same (the docId hash matches)
- The source column still exists and has the same type as when copied
- The source type isn't Text, because in that case it's nice if type guessing still happens
- The target column is empty, meaning it has type Any (we check earlier that it's not a formula column)

The info copied is the type, widgetOptions, and reference column settings (visible and display columns) but not conditional formatting.

The changes are mostly in a function `parsePasteForView` which is based on `BaseView._parsePasteForView` but ported to TypeScript in a new file `BaseView2.ts`.

Added a useraction `MaybeCopyDisplayFormula` exposing an existing Python function `maybe_copy_display_formula` because the target column needs a slightly different display formula.

Test Plan: Added a new nbrowser test file and fixture doc.

Reviewers: cyprien

Reviewed By: cyprien

Subscribers: jarek, dsagal

Differential Revision: https://phab.getgrist.com/D3344

sandbox/grist/useractions.py

@@ -1461,6 +1461,11 @@ class UserActions(object):
     self._do_doc_action(actions.BulkUpdateRecord(table_id, changed_rows,
                                                  {dst_col_id: changed_values}))
 
+  @useraction
+  def MaybeCopyDisplayFormula(self, src_col_ref, dst_col_ref):
+    src_col = self._docmodel.columns.table.get_record(src_col_ref)
+    dst_col = self._docmodel.columns.table.get_record(dst_col_ref)
+    self.maybe_copy_display_formula(src_col, dst_col)
 
   def maybe_copy_display_formula(self, src_col, dst_col):
     """