docs: add rustdoc comments to all module options

This part of an upcoming effort to generate documentation from code.

Pushing this out before that stage so that the JSON schema is fully documented.

src/modules/clipboard.rs

@@ -18,18 +18,34 @@ use tracing::{debug, error};
 
 #[derive(Debug, Deserialize, Clone)]
 pub struct ClipboardModule {
+    /// The icon to show on the bar widget button.
+    /// Supports [image](images) icons.
+    ///
+    /// **Default**: `󰨸`
     #[serde(default = "default_icon")]
     icon: String,
 
+    /// The size to render the icon at.
+    /// Note this only applies to image-type icons.
+    ///
+    /// **Default**: `32`
     #[serde(default = "default_icon_size")]
     icon_size: i32,
 
+    /// The maximum number of items to keep in the history,
+    /// and to show in the popup.
+    ///
+    /// **Default**: `10`
     #[serde(default = "default_max_items")]
     max_items: usize,
 
     // -- Common --
+    /// See [truncate options](module-level-options#truncate-mode).
+    ///
+    /// **Default**: `null`
     truncate: Option<TruncateMode>,
 
+    /// See [common options](module-level-options#common-options).
     #[serde(flatten)]
     pub common: Option<CommonConfig>,
 }