feat: add keyboard layout support

programs/src/music/main.cpp

@@ -415,8 +415,9 @@ static char ascii_lower(char c) {
     return (c >= 'A' && c <= 'Z') ? (char)(c + 32) : c;
 }
 
-static bool is_printable_ascii(char c) {
-    return c >= 32 && c < 127;
+static bool is_printable_byte(char c) {
+    unsigned char value = (unsigned char)c;
+    return value >= 32 && value != 127;
 }
 
 static bool str_contains_case_insensitive(const char* text, const char* needle) {
@@ -1448,7 +1449,7 @@ static bool handle_key(const montauk::abi::KeyEvent& key, bool& quit) {
             else g.filter_active = false;
             return true;
         }
-        if (!key.ctrl && !key.alt && is_printable_ascii(key.ascii)) {
+        if (!key.ctrl && !key.alt && is_printable_byte(key.ascii)) {
             append_filter_char(key.ascii);
             return true;
         }