[tools] refactor, use #!/bin/sh, update license files (#3998)

Signed-off-by: lizzie <lizzie@eden-emu.dev>
Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3998
Reviewed-by: crueter <crueter@eden-emu.dev>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>

hooks/pre-commit

@@ -1,5 +1,7 @@
-#!/bin/sh
+#!/bin/sh -e
 
+# SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
+# SPDX-License-Identifier: GPL-3.0-or-later
 # SPDX-FileCopyrightText: 2015 Citra Emulator Project
 # SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -10,20 +12,19 @@ paths_to_check="src/ CMakeLists.txt"
 
 # If there are whitespace errors, print the offending file names and fail.
 if ! git diff --cached --check -- $paths_to_check ; then
-    cat<<END
-
+    cat<<EOF
 Error: This commit would contain trailing spaces or tabs, which is against this repo's policy.
 Please correct those issues before committing. (Use 'git diff --check' for more details)
 If you know what you are doing, you can try 'git commit --no-verify' to bypass the check
-END
+EOF
     exit 1
 fi
 
 # Check for tabs, since tab-in-indent catches only those at the beginning of a line
 if git diff --cached -- $paths_to_check | egrep '^\+.*	'; then
-    cat<<END
+    cat<<EOF
 Error: This commit would contain a tab, which is against this repo's policy.
 If you know what you are doing, you can try 'git commit --no-verify' to bypass the check.
-END
+EOF
     exit 1
 fi