docs: mise à jour de la documentation pour l'accès au BuildContext dans les plugins

Author: raidos23

docs/ark_main_config.md

@@ -43,7 +43,7 @@ GUI shortcuts:
 
 ## Relationship to BuildContext
 
-The fields in `ark.yml` are mapped directly to the `BuildContext` data structure passed to engines:
+The fields in `ark.yml` are mapped directly to the `BuildContext` data structure passed to engines and BC plugins:
 
 | ark.yml field | BuildContext field |
 | :--- | :--- |

docs/dev_docs/ARK_BuildContext_v1.0.md

@@ -5,7 +5,9 @@ This document defines the data contract between ARK core and compilation engines
 ---
 
 ### **1. Definition**
-The `BuildContext` is a normalized data structure passed by ARK to an engine's `build_command` method.
+The `BuildContext` is a normalized data structure passed by ARK to:
+1.  An engine's `build_command` method.
+2.  BC (Before-Compilation) plugins via the `PreCompileContext`.
 
 - **Source Agnostic**: Engines do not read source files (`ark.yml`, lock files, etc.). They rely exclusively on this context.
 - **Reproducibility**: The context contains all project-level metadata required to generate a consistent build command, regardless of whether it was triggered from a live configuration or a lock file.

docs/how_to_create_a_bc_plugin.md

@@ -129,10 +129,22 @@ Key properties and methods.
 - `root`: Path object pointant vers la racine du workspace.
 - `name`: Nom du dossier workspace.
 - `config`: Dictionnaire complet de configuration (`bcasl.yml`).
+- `build_context`: Objet `BuildContext` contenant les paramètres de compilation (si disponible).
 - `file_patterns`: Patterns d'inclusion définis.
 - `exclude_patterns`: Patterns d'exclusion définis.
 - `iter_files(include, exclude)`: Itérateur optimisé (respecte les exclusions par défaut).
 
+Usage du BuildContext :
+```python
+def on_pre_compile(self, ctx: PreCompileContext) -> None:
+    if ctx.build_context:
+        # Accès au dossier de sortie défini dans ark.yml ou le verrou
+        output_dir = ctx.build_context.output_dir
+        ...
+```
+
+*Exemple concret : Le plugin **OutputCleaner** utilise `ctx.build_context.output_dir` pour vider le dossier de sortie avant la compilation.*
+
 Usage simplifié :
 ```python
 # Parcourt tous les fichiers du projet selon la config bcasl.yml