neteja tidy (29 → 0) i migració JA_* → Ja::

source/core/input/key_config.cpp

@@ -12,19 +12,19 @@
 
 // ── Singleton ────────────────────────────────────────────────────────────────
 
-KeyConfig* KeyConfig::instance_ = nullptr;
+KeyConfig* KeyConfig::instance = nullptr;
 
 void KeyConfig::init(const std::string& yaml_path) {
-    instance_ = new KeyConfig();
-    instance_->load(yaml_path);
+    instance = new KeyConfig();
+    instance->load(yaml_path);
 }
 
 void KeyConfig::destroy() {
-    delete instance_;
-    instance_ = nullptr;
+    delete instance;
+    instance = nullptr;
 }
 
-auto KeyConfig::get() -> KeyConfig* { return instance_; }
+auto KeyConfig::get() -> KeyConfig* { return instance; }
 
 // ── Carga del YAML ──────────────────────────────────────────────────────────