Add more defaults to the stdlib (#9606)

Continuing work towards #8988.

The first five commits were created using stubdefaulter on various Python versions; the following commits were all created manually by me to fix various problems. The main things this adds that weren't present in #9501 are:

- Defaults in Windows-only modules and Windows-only branches (because I'm running a Windows machine)
- Defaults in non-py311 branches
- Defaults for float parameters
- Defaults for overloads

stdlib/pydoc.pyi

@@ -88,19 +88,19 @@ class HTMLDoc(Doc):
         ) -> str: ...
         def multicolumn(self, list: list[_T], format: Callable[[_T], str]) -> str: ...
     else:
-        def heading(self, title: str, fgcol: str, bgcol: str, extras: str = ...) -> str: ...
+        def heading(self, title: str, fgcol: str, bgcol: str, extras: str = "") -> str: ...
         def section(
             self,
             title: str,
             fgcol: str,
             bgcol: str,
             contents: str,
-            width: int = ...,
-            prelude: str = ...,
-            marginalia: str | None = ...,
-            gap: str = ...,
+            width: int = 6,
+            prelude: str = "",
+            marginalia: str | None = None,
+            gap: str = " ",
         ) -> str: ...
-        def multicolumn(self, list: list[_T], format: Callable[[_T], str], cols: int = ...) -> str: ...
+        def multicolumn(self, list: list[_T], format: Callable[[_T], str], cols: int = 4) -> str: ...
 
     def bigsection(self, title: str, *args: Any) -> str: ...
     def preformat(self, text: str) -> str: ...