feat: Rich tables support for HTML backend (#2324)

* Rich tables support for HTML backend

Signed-off-by: Maksym Lysak <mly@zurich.ibm.com>

* Decoupling JATS backend from HTML backend, ways of creating tables changed significantly

Signed-off-by: Maksym Lysak <mly@zurich.ibm.com>

* updated and added tests

Signed-off-by: Maksym Lysak <mly@zurich.ibm.com>

* Refactored parse_table_data in html_backend into few smaller functions

Signed-off-by: Maksym Lysak <mly@zurich.ibm.com>

* Changing scope of few functions in html_backend.py, making them static, when possible

Signed-off-by: Maksym Lysak <mly@zurich.ibm.com>

* Fix for HTML tables that have tbody and/or thead, now these tables are also properly supported

Signed-off-by: Maksym Lysak <mly@zurich.ibm.com>

---------

Signed-off-by: Maksym Lysak <mly@zurich.ibm.com>
Co-authored-by: Maksym Lysak <mly@zurich.ibm.com>

tests/data/groundtruth/docling_v2/hyperlink_01.html.json

@@ -1,6 +1,6 @@
 {
   "schema_name": "DoclingDocument",
-  "version": "1.6.0",
+  "version": "1.7.0",
   "name": "hyperlink_01",
   "origin": {
     "mimetype": "text/html",