chore: rewrite the backend (not tested) (#203)

* wip: refactor

* refactor

* clean up

* .

* rename

* add relay auth

* .

* .

* optimize

* .

* clean up

* add encryption crate

* .

* .

* .

* .

* .

* add encryption crate

* .

* refactor nip4e

* .

* fix endless loop

* fix metadata fetching

crates/encryption/src/signer.rs

@@ -0,0 +1,9 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Default, Deserialize, Serialize)]
+pub enum SignerKind {
+    Encryption,
+    #[default]
+    User,
+    Auto,
+}