docs/qapidoc: add visit_paragraph() method

This transforms "formerly known as untagged sections" into our pure
intermediate rST format. These sections are already pure rST, so this
method doesn't do a whole lot except ensure appropriate newlines.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-ID: <20250311034303.75779-45-jsnow@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

docs/sphinx/qapidoc.py

@@ -130,6 +130,15 @@ def ensure_blank_line(self) -> None:
 
     # Transmogrification helpers
 
+    def visit_paragraph(self, section: QAPIDoc.Section) -> None:
+        # Squelch empty paragraphs.
+        if not section.text:
+            return
+
+        self.ensure_blank_line()
+        self.add_lines(section.text, section.info)
+        self.ensure_blank_line()
+
     def preamble(self, ent: QAPISchemaDefinition) -> None:
         """
         Generate option lines for QAPI entity directives.