Allow openapi generator to remove unknown files from output dir (#2281)

Fix #2273 
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----

> [!IMPORTANT]
> Add `REMOVE_DIR_BEHAVIOR` to `OpenApiLanguageFeatures` to allow
removal of unknown files from output directory.
> 
>   - **Behavior**:
> - Add `REMOVE_DIR_BEHAVIOR` constant to `OpenApiLanguageFeatures` in
`openapi/src/lib.rs`, allowing removal of unknown files from output
directory.
>   - **Code Structure**:
> - Comment out `dir_writer` module import in
`language_client_codegen/src/lib.rs`.
> 
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Author: antoniosarosi

engine/generators/languages/openapi/src/lib.rs

@@ -1,6 +1,8 @@
 use std::hash::Hash;
 
-use dir_writer::{FileCollector, GeneratorArgs, IntermediateRepr, LanguageFeatures};
+use dir_writer::{
+    FileCollector, GeneratorArgs, IntermediateRepr, LanguageFeatures, RemoveDirBehavior,
+};
 use indexmap::IndexMap;
 use serde::Serialize;
 
@@ -19,6 +21,10 @@ impl LanguageFeatures for OpenApiLanguageFeatures {
         "openapi"
     }
 
+    /// OpenAPI codegen creates a lot of files that BAML can't know about in
+    /// advance, so we allow removing them.
+    const REMOVE_DIR_BEHAVIOR: RemoveDirBehavior = RemoveDirBehavior::Unsafe;
+
     const CONTENT_PREFIX: &'static str = r#"
 ###############################################################################
 #

engine/language_client_codegen/src/lib.rs

@@ -14,7 +14,7 @@ use regex::Regex;
 use sugar_path::SugarPath;
 use version_check::{check_version, GeneratorType, VersionCheckMode};
 
-mod dir_writer;
+// mod dir_writer;
 // mod go;
 // pub mod openapi;
 // mod python;