asked the clanker to change the arcidecture a bit

crates/common/Cargo.toml

@@ -9,3 +9,4 @@ path = "src/lib.rs"
 
 [dependencies]
 iced = { workspace = true }
+toml = { workspace = true }

crates/common/src/lib.rs

@@ -1,15 +1,16 @@
 //! Barbar's protocol crate: the types that cross crate boundaries.
 //!
-//! Nothing here may reference app-level types (`Message`, `Cmd`, `Msg`,
+//! Nothing here may reference app-level types (`Message`, `Msg`,
 //! layer-shell effects). `common` is the hub every other crate depends on,
 //! so it must stay acyclic and pure.
 
 use std::any::Any;
+use std::error::Error;
 use std::fmt;
 use std::sync::Arc;
 
 use iced::window;
-use iced::{Element, Task};
+use iced::{Element, Rectangle, Task};
 
 // ---------------------------------------------------------------------------
 // Service model
@@ -95,12 +96,16 @@ impl fmt::Debug for ModuleMsg {
     }
 }
 
-/// What a module asks the app to do. Modules never name app types; the app
-/// maps these into its own effects (`Cmd`).
+/// What a module asks the app to do — the single effect vocabulary shared by
+/// modules and app, so mapping module output into a `Message` is a plain
+/// `.map(Message::Effect)` with no mirror enum.
 #[derive(Debug, Clone)]
 pub enum ModuleEffect {
     /// Toggle a popup for the given module id (element id anchors it).
     RequestPopup(String, String),
+    /// A widget-tree pass reported a module's laid-out bounds; anchor the
+    /// popup there. App-internal, but one effect type keeps routing trivial.
+    BoundsFound(String, Rectangle),
     /// Request removal of the popup surface.
     ClosePopup(window::Id),
 }
@@ -124,4 +129,11 @@ pub trait BarModule: Send {
     fn popup_size(&self) -> Option<(u32, u32)> {
         None
     }
+
+    /// Digest config from `module.{module-id}`. Error is boxed because this
+    /// runs through `dyn BarModule`; each impl keeps its own concrete error
+    /// internally and may surface it pre-box via its constructor instead.
+    fn config(&mut self, _config: toml::Table) -> Result<(), Box<dyn Error>> {
+        Ok(())
+    }
 }