Fix locale-dependent float printing in GGUF metadata (#17331)

* Set C locale for consistent float formatting across all binaries.

* Add C locale setting to all tools binaries

Add std::setlocale(LC_NUMERIC, "C") to all 16 binaries in the tools/
directory to ensure consistent floating-point formatting.

* Apply suggestion from @JohannesGaessler

---------

Co-authored-by: Johannes Gäßler <johannesg@5d6.de>

tools/export-lora/export-lora.cpp

@@ -5,6 +5,7 @@
 #include "arg.h"
 #include "common.h"
 
+#include <clocale>
 #include <map>
 #include <vector>
 #include <string>
@@ -411,6 +412,8 @@ static void print_usage(int, char ** argv) {
 }
 
 int main(int argc, char ** argv) {
+    std::setlocale(LC_NUMERIC, "C");
+
     common_params params;
 
     params.out_file = "ggml-lora-merged-f16.gguf";