fix: resolve CodeChecker findings and add CodeChecker ignore rules

- Refactor cause in draw_game_over_screen to an immediately invoked lambda, eliminating dead store warning
- Rename sound effect files to standard-compliant names without double underscores to prevent reserved macro warnings in soundbank.h
- Update source/game_audio.cpp to use clean SFX_* macro identifiers
- Add codechecker_skip.txt to ignore external devkitPro toolchain headers
- Ignore .codechecker/ output artifacts directory in .gitignore
- Update AGENTS.md file tree and sound asset references

source/game_audio.cpp

@@ -8,16 +8,16 @@ void audio_setup(AudioContext &audio) {
 
     mmLoad(MOD_0RIGIN);
 
-    mmLoadEffect(SFX_332629__TREASURESOUNDS__ITEM_PICKUP);
+    mmLoadEffect(SFX_PICKUP);
     mmLoadEffect(SFX_BOOM);
-    mmLoadEffect(SFX_167127__CRISSTANZA__PAUSE);
-    mmLoadEffect(SFX_167126__CRISSTANZA__UNPAUSE);
-    mmLoadEffect(SFX_273792__PACOMAV__PLOP);
-    mmLoadEffect(SFX_73750__TIMBRE__REMIX_OF_BENBONCAN_SAD_TROMBONE_MORE_WAH_BRIGHT_DE_CLICKED);
+    mmLoadEffect(SFX_PAUSE);
+    mmLoadEffect(SFX_UNPAUSE);
+    mmLoadEffect(SFX_PLOP);
+    mmLoadEffect(SFX_SAD_TROMBONE);
     mmLoadEffect(SFX_DENIED);
 
     audio.sfx_pickup = {
-        { SFX_332629__TREASURESOUNDS__ITEM_PICKUP },
+        { SFX_PICKUP },
         static_cast<int>(1.0F * (1 << 10)),
         0,
         255,
@@ -33,7 +33,7 @@ void audio_setup(AudioContext &audio) {
     };
 
     audio.sfx_pause = {
-        { SFX_167127__CRISSTANZA__PAUSE },
+        { SFX_PAUSE },
         static_cast<int>(1.0F * (1 << 10)),
         2,
         255,
@@ -41,7 +41,7 @@ void audio_setup(AudioContext &audio) {
     };
 
     audio.sfx_unpause = {
-        { SFX_167126__CRISSTANZA__UNPAUSE },
+        { SFX_UNPAUSE },
         static_cast<int>(1.0F * (1 << 10)),
         3,
         255,
@@ -49,7 +49,7 @@ void audio_setup(AudioContext &audio) {
     };
 
     audio.sfx_plop = {
-        { SFX_273792__PACOMAV__PLOP },
+        { SFX_PLOP },
         static_cast<int>(1.0F * (1 << 10)),
         4,
         128,
@@ -57,7 +57,7 @@ void audio_setup(AudioContext &audio) {
     };
 
     audio.sfx_fail = {
-        { SFX_73750__TIMBRE__REMIX_OF_BENBONCAN_SAD_TROMBONE_MORE_WAH_BRIGHT_DE_CLICKED },
+        { SFX_SAD_TROMBONE },
         static_cast<int>(1.0F * (1 << 10)),
         4,
         255,