add remove entry and get directory handle to file_system

gleam.toml

···
 name = "plinth"
-version = "0.5.3"
+version = "0.5.4"
 description = "Bindings to Node.js and browser platform APIs"
 target = "javascript"
 

src/file_system_ffi.mjs

···
   }
 }
 
-export async function getFileHandle(directoryHandle, name) {
+export function name(handle) {
+  return handle.name
+}
+
+export async function getDirectoryHandle(directoryHandle, name, create) {
   try {
-    return new Ok(await directoryHandle.getFileHandle(name));
+    return new Ok(await directoryHandle.getDirectoryHandle(name, { create }));
+  } catch (error) {
+    return new Error(error.toString());
+  }
+}
+
+export async function getFileHandle(directoryHandle, name, create) {
+  try {
+    return new Ok(await directoryHandle.getFileHandle(name, { create }));
+  } catch (error) {
+    return new Error(error.toString());
+  }
+}
+
+export async function removeEntry(directoryHandle, name, recursive) {
+  try {
+    return new Ok(await directoryHandle.removeEntry(name, { recursive }));
   } catch (error) {
     return new Error(error.toString());
   }

src/plinth/browser/file_system.gleam

···
 import gleam/javascript/promise.{type Promise}
 import plinth/browser/file.{type File}
 
-pub type DirectoryHandle
+pub type Handle(a)
+
+pub type D
+
+pub type F
+
+pub type DirectoryHandle =
+  Handle(D)
 
-pub type FileHandle
+pub type FileHandle =
+  Handle(F)
 
 @external(javascript, "../../file_system_ffi.mjs", "showDirectoryPicker")
 pub fn show_directory_picker() -> Promise(Result(DirectoryHandle, String))
 
+@external(javascript, "../../file_system_ffi.mjs", "name")
+pub fn name(handle: Handle(a)) -> String
+
+@external(javascript, "../../file_system_ffi.mjs", "getDirectoryHandle")
+pub fn get_directory_handle(
+  handle: DirectoryHandle,
+  name: String,
+  create: Bool,
+) -> Promise(Result(DirectoryHandle, String))
+
 @external(javascript, "../../file_system_ffi.mjs", "getFileHandle")
 pub fn get_file_handle(
   handle: DirectoryHandle,
   name: String,
+  create: Bool,
 ) -> Promise(Result(FileHandle, String))
+
+@external(javascript, "../../file_system_ffi.mjs", "removeEntry")
+pub fn remove_entry(
+  handle: DirectoryHandle,
+  name: String,
+  create: Bool,
+) -> Promise(Result(Nil, String))
 
 @external(javascript, "../../file_system_ffi.mjs", "allEntries")
 pub fn all_entries(