Fase 1b: rename d'entitats i metodes virtuals a CamelCase/camelBack

Tots els tipus d'entitat passen del catala a l'angles seguint el
.clang-tidy del projecte (tipus en CamelCase, metodes en camelBack,
membres en lower_case amb sufix _).

Renames de tipus:
- Entitat -> Entity (core/entities/entity.hpp)
- Nau -> Ship (game/entities/ship.{hpp,cpp})
- Enemic -> Enemy (game/entities/enemy.{hpp,cpp})
- Bala -> Bullet (game/entities/bullet.{hpp,cpp})
- TipusEnemic -> EnemyType
- AnimacioEnemic -> EnemyAnimation

Metodes virtuals (s'aplica a tot el codi, no nomes a entitats):
- actualitzar -> update
- dibuixar -> draw
- inicialitzar -> init
- processar_input -> processInput
- esta_actiu -> isActive
- es_collidable -> isCollidable
- get_collision_radius -> getCollisionRadius

Getters comuns:
- get_centre -> getCenter
- get_angle -> getAngle
- get_brightness -> getBrightness
- get_forma -> getShape

Metodes especifics:
- esta_viva -> isAlive
- esta_tocada -> isHit
- es_invulnerable -> isInvulnerable
- get_velocitat_vector -> getVelocityVector
- set_centre -> setCenter
- marcar_tocada -> markHit
- aplicar_fisica -> applyPhysics
- get_tipus -> getType

Camps privats:
- centre_ -> center_
- velocitat_ -> velocity_
- forma_ -> shape_
- esta_tocada_ -> is_hit_
- tipus_ -> type_

L'import d'audio/input d'AEEA quedara coherent (mateix estil).
Diff net: 30 fitxers, +437/-437 (la majoria es renames simetrics).

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

source/core/graphics/shape.cpp

@@ -11,7 +11,7 @@
 namespace Graphics {
 
 Shape::Shape(const std::string& filepath)
-    : centre_({.x = 0.0F, .y = 0.0F}),
+    : center_({.x = 0.0F, .y = 0.0F}),
       escala_defecte_(1.0F),
       nom_("unnamed") {
     carregar(filepath);
@@ -124,11 +124,11 @@ void Shape::parse_center(const std::string& value) {
     size_t comma = val.find(',');
     if (comma != std::string::npos) {
         try {
-            centre_.x = std::stof(trim(val.substr(0, comma)));
-            centre_.y = std::stof(trim(val.substr(comma + 1)));
+            center_.x = std::stof(trim(val.substr(0, comma)));
+            center_.y = std::stof(trim(val.substr(comma + 1)));
         } catch (...) {
             std::cerr << "[Shape] Warning: centre invàlid, usant (0,0)" << '\n';
-            centre_ = {.x = 0.0F, .y = 0.0F};
+            center_ = {.x = 0.0F, .y = 0.0F};
         }
     }
 }