make BackgroundProcessorConfig docs conditional on futures feature

Author: Anyitechs

lightning-background-processor/src/lib.rs

@@ -1160,7 +1160,9 @@ impl BackgroundProcessor {
 	}
 }
 
-/// Configuration for both synchronous [`BackgroundProcessor`] and asynchronous [`process_events_async`] event processing.
+/// Configuration for synchronous [`BackgroundProcessor`]
+#[cfg_attr(feature = "futures", doc = "and asynchronous [`process_events_async`]")]
+/// event processing.
 ///
 /// This configuration holds all components needed for background processing,
 /// including required components (like the channel manager and peer manager) and optional
@@ -1169,9 +1171,17 @@ impl BackgroundProcessor {
 /// The configuration can be constructed using [`BackgroundProcessorBuilder`], which provides
 /// a convenient builder pattern for setting up both required and optional components.
 ///
-/// This same configuration can be used for both:
+/// This same configuration can be used for
+#[cfg_attr(
+	not(feature = "futures"),
+	doc = "creating a [`BackgroundProcessor`] via [`BackgroundProcessor::from_config`]."
+)]
+#[cfg_attr(
+	feature = "futures",
+	doc = "both:
 /// * Creating a [`BackgroundProcessor`] via [`BackgroundProcessor::from_config`]
-/// * Running the async variant of the background processor via [`process_events_async`]
+/// * Running the async variant of the background processor via [`process_events_async`]"
+)]
 ///
 /// # Example
 /// ```
@@ -1192,8 +1202,12 @@ impl BackgroundProcessor {
 /// // Use with BackgroundProcessor
 /// let processor = BackgroundProcessor::from_config(config);
 ///
+#[cfg_attr(
+	feature = "futures",
+	doc = "
 /// // Or use with async processing
-/// process_events_async(config, sleeper, mobile_interruptable_platform, fetch_time).await?;
+/// process_events_async(config, sleeper, mobile_interruptable_platform, fetch_time).await?;"
+)]
 /// ```
 #[cfg(feature = "std")]
 pub struct BackgroundProcessorConfig<