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/imaplib.pyi

@@ -44,8 +44,8 @@ class IMAP4:
         def __init__(self, host: str = "", port: int = 143, timeout: float | None = None) -> None: ...
         def open(self, host: str = "", port: int = 143, timeout: float | None = None) -> None: ...
     else:
-        def __init__(self, host: str = ..., port: int = ...) -> None: ...
-        def open(self, host: str = ..., port: int = ...) -> None: ...
+        def __init__(self, host: str = "", port: int = 143) -> None: ...
+        def open(self, host: str = "", port: int = 143) -> None: ...
 
     def __getattr__(self, attr: str) -> Any: ...
     host: str
@@ -123,18 +123,18 @@ class IMAP4_SSL(IMAP4):
     else:
         def __init__(
             self,
-            host: str = ...,
-            port: int = ...,
-            keyfile: str | None = ...,
-            certfile: str | None = ...,
-            ssl_context: SSLContext | None = ...,
+            host: str = "",
+            port: int = 993,
+            keyfile: str | None = None,
+            certfile: str | None = None,
+            ssl_context: SSLContext | None = None,
         ) -> None: ...
     sslobj: SSLSocket
     file: IO[Any]
     if sys.version_info >= (3, 9):
         def open(self, host: str = "", port: int | None = 993, timeout: float | None = None) -> None: ...
     else:
-        def open(self, host: str = ..., port: int | None = ...) -> None: ...
+        def open(self, host: str = "", port: int | None = 993) -> None: ...
 
     def ssl(self) -> SSLSocket: ...
 
@@ -148,7 +148,7 @@ class IMAP4_stream(IMAP4):
     if sys.version_info >= (3, 9):
         def open(self, host: str | None = None, port: int | None = None, timeout: float | None = None) -> None: ...
     else:
-        def open(self, host: str | None = ..., port: int | None = ...) -> None: ...
+        def open(self, host: str | None = None, port: int | None = None) -> None: ...
 
 class _Authenticator:
     mech: Callable[[bytes], bytes | bytearray | memoryview | str | None]