f: Remove global PATHS_PLACEHOLDER

Author: shaavan

lightning/src/onion_message/messenger.rs

@@ -432,12 +432,6 @@ pub enum MessageSendInstructions {
 	},
 }
 
-/// A placeholder value used for paths within the codebase.
-///
-/// PATHS_PLACEHOLDER` is temporarily used as a default value in situations
-/// where a path index is required but has not yet been assigned or initialized.
-pub const PATHS_PLACEHOLDER: usize = 0;
-
 /// Represents the types of [`BlindedMessagePath`] that can be created.
 ///
 /// This struct allows to specify the properties of a Blinded Path before creating it.
@@ -448,6 +442,27 @@ pub struct BlindedPathParams {
 	pub is_compact: bool,
 }
 
+impl BlindedPathParams {
+	/// Number of paths to be calculated, used by default throughout the codebase.
+	const DEFAULT_PATHS: usize = 3;
+
+	/// Create [`BlindedPathParams`] with default number of paths.
+	pub fn new(is_compact: bool) -> Self {
+		Self {
+			paths: Self::DEFAULT_PATHS,
+			is_compact,
+		}
+	}
+
+	/// Create [`BlindedPathParams`] with custom number of paths.
+	pub fn new_with_paths(paths: usize, is_compact: bool) -> Self {
+		Self {
+			paths,
+			is_compact,
+		}
+	}
+}
+
 /// A trait defining behavior for routing an [`OnionMessage`].
 pub trait MessageRouter {
 	/// Returns a route for sending an [`OnionMessage`] to the given [`Destination`].