[Peek]Peek and Monaco file encoding issues are solved with a encoding detector (#26955)

* [Peek] Peek and Monaco file encoding issues are solved with a encoding detector.

* [Peek] Monaco encoding parameter is moved to another function.

* [Peek] NOTICE.md update.

* [Peek] Spell Check update.

* UTF-Unknown is added to Nuget list in Notice.md

* System.Text.Encoding.CodePages is added to Nuget list in Notice.md

* [Peek] Unncessary mainfest files are deleted.

* [Peek ] Unncessary mainfest file are deleted.

* [Peek] Encoding null check is added.

* Update NOTICE.md

* Update NOTICE.md

* ci: Add signing to UtfUnknown

.github/actions/spell-check/expect.txt

@@ -388,6 +388,7 @@ Deact
 debian
 debugbreak
 DECLAR
+declatory
 declspec
 decryptor
 Dedup
@@ -1158,6 +1159,8 @@ MOUSEWHEEL
 MOVESIZEEND
 MOVESIZESTART
 mozilla
+MOZILLAPL
+MOZPL
 mpmc
 MRM
 MRT
@@ -1230,6 +1233,7 @@ netcore
 netcoreapp
 netcpl
 netframework
+Netscape
 netsetup
 netsh
 Neue
@@ -1238,6 +1242,7 @@ newdev
 newitem
 newpath
 newrow
+newsgroups
 Newtonsoft
 nielslaute
 NIF