feat: lnbits ln backend

fix: check webhook url is valid

crates/cdk-lnbits/src/error.rs

@@ -0,0 +1,23 @@
+//! Error for Strike ln backend
+
+use thiserror::Error;
+
+/// Strike Error
+#[derive(Debug, Error)]
+pub enum Error {
+    /// Invoice amount not defined
+    #[error("Unknown invoice amount")]
+    UnknownInvoiceAmount,
+    /// Unknown invoice
+    #[error("Unknown invoice")]
+    UnknownInvoice,
+    /// Anyhow error
+    #[error(transparent)]
+    Anyhow(#[from] anyhow::Error),
+}
+
+impl From<Error> for cdk::cdk_lightning::Error {
+    fn from(e: Error) -> Self {
+        Self::Lightning(Box::new(e))
+    }
+}