(feat): rename example-usage to just example

(feat): add the example's web-client dist folder to a gitignore
(fix): format issues
(fix): a lot of duplicate code

example/server/src/keys.rs

@@ -0,0 +1,50 @@
+use std::fs;
+
+use mtp::crypto::kem::HybridKem;
+use mtp::crypto::{Ed25519Signer, Keyring, MlDsaSigner};
+
+pub fn load_or_generate_host_keys(
+    path: &str,
+) -> Result<(u64, Keyring), Box<dyn std::error::Error>> {
+    if let Ok(data) = fs::read_to_string(path) {
+        let json: serde_json::Value = serde_json::from_str(&data)?;
+        let hid = json["host_id"].as_u64().unwrap_or(1);
+        let keyring = Keyring::from_bytes(&hex::decode(json["keyring"].as_str().unwrap())?)?;
+        println!("Loaded host keys (ID: {})", hid);
+        return Ok((hid, keyring));
+    }
+
+    let (_ed_signer, sig_sk, sig_pk) = Ed25519Signer::generate();
+    let (_pq_signer, sig_pq_sk, sig_pq_pk) = MlDsaSigner::generate();
+    let (kem_sk, kem_pk) = HybridKem::generate_keypair();
+    let keyring = Keyring::new(kem_pk, kem_sk, sig_pq_pk, sig_pq_sk, sig_pk, sig_sk);
+
+    let json = serde_json::json!({
+        "host_id": 1,
+        "keyring": hex::encode(keyring.to_bytes()),
+    });
+    fs::write(path, serde_json::to_string_pretty(&json)?)?;
+    println!("Generated host keys -> {path}");
+    Ok((1u64, keyring))
+}
+
+pub fn export_host_public_keys(host_keyring: &Keyring) -> Result<(), Box<dyn std::error::Error>> {
+    let public_key_bundle_hex = hex::encode(host_keyring.public_key_bundle().as_bytes());
+
+    fs::write("host_public_key_bundle.hex", &public_key_bundle_hex)?;
+    fs::create_dir_all("web-client/public")?;
+    fs::write(
+        "web-client/public/host_public_key_bundle.hex",
+        &public_key_bundle_hex,
+    )?;
+    fs::write(
+        "host_enc_kem_pk.bin",
+        host_keyring.kem_public_key.as_bytes(),
+    )?;
+    fs::write("host_sig_pk.bin", host_keyring.sig_cl_public_key.as_bytes())?;
+    fs::write(
+        "host_sig_pq_pk.bin",
+        host_keyring.sig_pq_public_key.as_bytes(),
+    )?;
+    Ok(())
+}