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/ftplib.pyi

@@ -56,12 +56,12 @@ class FTP:
     else:
         def __init__(
             self,
-            host: str = ...,
-            user: str = ...,
-            passwd: str = ...,
-            acct: str = ...,
+            host: str = "",
+            user: str = "",
+            passwd: str = "",
+            acct: str = "",
             timeout: float = ...,
-            source_address: tuple[str, int] | None = ...,
+            source_address: tuple[str, int] | None = None,
         ) -> None: ...
 
     def connect(
@@ -136,15 +136,15 @@ class FTP_TLS(FTP):
     else:
         def __init__(
             self,
-            host: str = ...,
-            user: str = ...,
-            passwd: str = ...,
-            acct: str = ...,
-            keyfile: str | None = ...,
-            certfile: str | None = ...,
-            context: SSLContext | None = ...,
+            host: str = "",
+            user: str = "",
+            passwd: str = "",
+            acct: str = "",
+            keyfile: str | None = None,
+            certfile: str | None = None,
+            context: SSLContext | None = None,
             timeout: float = ...,
-            source_address: tuple[str, int] | None = ...,
+            source_address: tuple[str, int] | None = None,
         ) -> None: ...
     ssl_version: int
     keyfile: str | None