refactor(log): migra core/input i core/audio a Log::

- gamepad_manager.cpp (12 logs): connect/disconnect com a info,
  errors d'open/init com a error, warning per BD no carregada.
- key_config.cpp (5 logs): error per arxius malformats, info
  per al recompte de bindings carregats.
- gamepad_bindings.cpp (4 logs): error/info anàleg.
- audio_effects.cpp (2 errors de format).
- sound_effects_config.cpp (3 logs): warn quan no hi ha presets,
  error de parse.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

source/core/input/gamepad_bindings.cpp

@@ -3,12 +3,12 @@
 #include <algorithm>
 #include <array>
 #include <fstream>
-#include <iostream>
 #include <sstream>
 #include <string_view>
 #include <utility>
 
 #include "external/fkyaml_node.hpp"
+#include "utils/log.hpp"
 
 namespace {
 
@@ -167,8 +167,7 @@ void GamepadBindings::load(const std::string& file_path) {
     try {
         auto yaml = fkyaml::node::deserialize(CONTENT);
         if (!yaml.contains("gamepads") || !yaml["gamepads"].is_sequence()) {
-            std::cerr << "GamepadBindings: secció 'gamepads' absent o invàlida a "
-                      << file_path << '\n';
+            Log::error("GamepadBindings", "secció 'gamepads' absent o invàlida a {}", file_path);
             return;
         }
         for (const auto& entry : yaml["gamepads"]) {
@@ -188,11 +187,9 @@ void GamepadBindings::load(const std::string& file_path) {
             }
             configs_.push_back(std::move(cfg));
         }
-        std::cout << "GamepadBindings: " << configs_.size() << " mandos carregats de "
-                  << file_path << '\n';
+        Log::info("GamepadBindings", "{} mandos carregats de {}", configs_.size(), file_path);
     } catch (const std::exception& e) {
-        std::cerr << "GamepadBindings: error parsejant " << file_path << ": "
-                  << e.what() << '\n';
+        Log::error("GamepadBindings", "error parsejant {}: {}", file_path, e.what());
     }
 }
 
@@ -215,7 +212,7 @@ auto GamepadBindings::save() -> bool {
 
     std::ofstream file(file_path_, std::ios::binary);
     if (!file) {
-        std::cerr << "GamepadBindings: no es pot escriure " << file_path_ << '\n';
+        Log::error("GamepadBindings", "no es pot escriure {}", file_path_);
         return false;
     }
     file << out.str();