Update _curses module for 3.14 (#14113)

Author: sobolevn

stdlib/@tests/stubtest_allowlists/darwin-py314.txt

@@ -2,7 +2,6 @@
 # TODO: New errors in Python 3.14 that need to be fixed or moved below
 # ====================================================================
 
-_curses.assume_default_colors
 _posixsubprocess.fork_exec
 asyncio.tools
 asyncio.unix_events.__all__

stdlib/@tests/stubtest_allowlists/linux-py314.txt

@@ -2,7 +2,6 @@
 # TODO: New errors in Python 3.14 that need to be fixed or moved below
 # ====================================================================
 
-_curses.assume_default_colors
 _posixsubprocess.fork_exec
 asyncio.tools
 asyncio.unix_events.__all__

stdlib/_curses.pyi

@@ -304,6 +304,9 @@ def has_colors() -> bool: ...
 if sys.version_info >= (3, 10):
     def has_extended_color_support() -> bool: ...
 
+if sys.version_info >= (3, 14):
+    def assume_default_colors(fg: int, bg: int, /) -> None: ...
+
 def has_ic() -> bool: ...
 def has_il() -> bool: ...
 def has_key(key: int, /) -> bool: ...