New Docs: Updated templates with old design. (#32002)

* New Docs: Updated templates with old design.

* New Docs: Remove (nullable) from methods that return null.

* New Docs: Improved parameters table.

* New Docs: Removed unused code from templates.

* New Docs: Fixed h2/h3 in dark mode.

* New Docs: Fixed Import.

* New Docs: Fixed navigation scroll resetting.