Update SCons 4.8.1 to 4.9.1 (#18069)

Summary of the issue:

Update SCons from 4.8.1 to 4.9.1 to apply the latest security fixes.
https://github.com/SCons/scons/releases/tag/4.9.1
Description of user facing changes

none
Description of development approach

The Scons version in pyproject.toml and uv.lock has been updated to the latest stable version 4.9.1.

Author: dpy013

pyproject.toml

@@ -301,7 +301,7 @@ members = [
 dev = [
 	"nvda-misc-deps",
 	# NVDA's build system is SCons
-	"SCons==4.8.1",
+	"SCons==4.9.1",
 	# Packaging NVDA
 	"py2exe==0.13.0.2",
 	"setuptools~=72.0",

user_docs/en/changes.md

@@ -11,7 +11,6 @@
 ### Changes
 
 * Component updates:
-  * Updated NSIS to 3.11 (#18027, @dpy013)
   * Updated LibLouis Braille translator to [3.34.0](https://github.com/liblouis/liblouis/releases/tag/v3.34.0). (#18227, @LeonarddeR, @codeofdusk)
     * Added new tables for Biblical Hebrew as well as for Russian 6 dot computer braille and Thai Grade 2.
     * Substantial updates to Lithuanian braille tables.
@@ -33,6 +32,8 @@
 Please refer to [the developer guide](https://www.nvaccess.org/files/nvda/documentation/developerGuide.html#API) for information on NVDA's API deprecation and removal process.
 
 * Component updates:
+  * Updated SCons to 4.9.1. (#18069, @dpy013)
+  * Updated NSIS to 3.11 (#18027, @dpy013)
   * Updated Ruff to 0.11.12. (#17671)
   * Updated pre-commit to 4.2.0. (#17671)
   * Updated pyright to 1.1.401. (#17671)