feat(egui): begin development of `egui-actions` crate

The purpose of this new crate is to provide a system for managing
actions that can be bound to a key and to derive `egui` menus to invoke
them.

I haven't moved all relevant code from `topola-egui` (in particular,
`Switch` and `Trigger` structs) to this crate yet.

crates/egui-actions/Cargo.toml

@@ -0,0 +1,17 @@
+# SPDX-FileCopyrightText: 2024 Topola contributors
+#
+# SPDX-License-Identifier: MIT
+
+[package]
+name = "egui-actions"
+version = "0.1.0"
+edition = "2021"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+egui = "0.29"
+proc-macro2 = "1.0"
+quote = "1.0"
+syn = "2.0"

crates/egui-actions/src/implementation.rs

@@ -0,0 +1,47 @@
+// SPDX-FileCopyrightText: 2025 Topola contributors
+//
+// SPDX-License-Identifier: MIT
+
+use proc_macro2::TokenStream;
+use quote::quote;
+use syn::{Data, DeriveInput, Field, Fields};
+
+pub(super) fn impl_derive_actions(input: &DeriveInput) -> TokenStream {
+    let name = &input.ident;
+    let new_body = impl_new_body(&input.data);
+
+    quote! {
+        impl #name {
+            pub fn new(tr: &Translator) -> Self {
+                #new_body
+            }
+        }
+    }
+}
+
+pub(super) fn impl_new_body(data: &Data) -> TokenStream {
+    match data {
+        Data::Struct(data) => match &data.fields {
+            Fields::Named(fields) => {
+                let fields = fields.named.iter().map(impl_new_field);
+
+                quote! {
+                    Self {
+                        #(#fields)*
+                    }
+                }
+            }
+            _ => unimplemented!(),
+        },
+        _ => unimplemented!(),
+    }
+}
+
+pub(super) fn impl_new_field(field: &Field) -> TokenStream {
+    let name = &field.ident;
+    let typ = &field.ty;
+
+    quote! {
+        #name: #typ::new(tr),
+    }
+}

crates/egui-actions/src/lib.rs

@@ -0,0 +1,14 @@
+// SPDX-FileCopyrightText: 2024 Topola contributors
+//
+// SPDX-License-Identifier: MIT
+
+use proc_macro::TokenStream;
+use syn::DeriveInput;
+
+mod implementation;
+
+#[proc_macro_derive(Actions)]
+pub fn derive_actions(input: TokenStream) -> TokenStream {
+    let input = syn::parse_macro_input!(input as DeriveInput);
+    implementation::impl_derive_actions(&input).into()
+}

crates/topola-egui/Cargo.toml

@@ -17,6 +17,7 @@ xdg-portal = ["rfd/async-std", "rfd/xdg-portal"]
 [dependencies]
 derive-getters.workspace = true
 egui = "0.29"
+egui-actions.path = "../egui-actions"
 fluent-templates = "0.11"
 geo.workspace = true
 icu_experimental = "0.2"

crates/topola-egui/src/action.rs

@@ -32,7 +32,6 @@ impl Action {
         )
     }
 
-    #[inline]
     pub fn into_trigger(self) -> Trigger {
         Trigger {
             action: self,
@@ -40,7 +39,6 @@ impl Action {
         }
     }
 
-    #[inline(always)]
     pub fn into_switch(self) -> Switch {
         Switch { action: self }
     }

crates/topola-egui/src/actions.rs

@@ -8,6 +8,7 @@ use crate::{
 };
 
 use egui::{Context, Ui};
+use egui_actions::Actions;
 use topola::autorouter::AutorouterOptions;
 
 pub struct FileActions {
@@ -299,6 +300,7 @@ impl HelpActions {
     }
 }
 
+#[derive(Actions)]
 pub struct Actions {
     pub file: FileActions,
     pub edit: EditActions,
@@ -307,16 +309,3 @@ pub struct Actions {
     pub inspect: InspectActions,
     pub help: HelpActions,
 }
-
-impl Actions {
-    pub fn new(tr: &Translator) -> Self {
-        Self {
-            file: FileActions::new(tr),
-            edit: EditActions::new(tr),
-            place: PlaceActions::new(tr),
-            route: RouteActions::new(tr),
-            inspect: InspectActions::new(tr),
-            help: HelpActions::new(tr),
-        }
-    }
-}

crates/topola-egui/src/menu_bar.rs

@@ -15,7 +15,6 @@ use topola::{
 };
 
 use crate::{
-    action::{Action, Switch, Trigger},
     actions::Actions,
     app::{execute, handle_file},
     translator::Translator,